Refactor docs about contributions to CONTRIBUTING.md.

Per the review comments.

CONTRIBUTING.md

@@ -21,8 +21,16 @@ accept your pull requests.
 
 ## Contributing A Patch
 
-1. Submit an issue describing your proposed change to the repo in question.
-1. The repo owner will respond to your issue promptly.
+1. Submit an issue describing your proposed change to the
+   [issue tracker](https://github.com/google/googletest).
+1. Please don't mix more than one logical change per submittal,
+   because it makes the history hard to follow. If you want to make a
+   change that doesn't have a corresponding issue in the issue
+   tracker, please create one.
+1. Also, coordinate with team members that are listed on the issue in
+   question. This ensures that work isn't being duplicated and
+   communicating your plan early also generally leads to better
+   patches.
 1. If your proposed change is accepted, and you haven't already done so, sign a
    Contributor License Agreement (see details above).
 1. Fork the desired repo, develop and test your code changes.
@@ -31,7 +39,122 @@ accept your pull requests.
 1. Ensure that your code has an appropriate set of unit tests which all pass.
 1. Submit a pull request.
 
+If you are a Googler, it is preferable to first create an internal change and
+have it reviewed and submitted, and then create an upstreaming pull
+request here. 
+
+## The Google Test and Google Mock Communities ##
+
+The Google Test community exists primarily through the
+[discussion group](http://groups.google.com/group/googletestframework)
+and the GitHub repository.
+Likewise, the Google Mock community exists primarily through their own
+[discussion group](http://groups.google.com/group/googlemock).
+You are definitely encouraged to contribute to the
+discussion and you can also help us to keep the effectiveness of the
+group high by following and promoting the guidelines listed here.
+
+### Please Be Friendly ###
+
+Showing courtesy and respect to others is a vital part of the Google
+culture, and we strongly encourage everyone participating in Google
+Test development to join us in accepting nothing less. Of course,
+being courteous is not the same as failing to constructively disagree
+with each other, but it does mean that we should be respectful of each
+other when enumerating the 42 technical reasons that a particular
+proposal may not be the best choice. There's never a reason to be
+antagonistic or dismissive toward anyone who is sincerely trying to
+contribute to a discussion.
+
+Sure, C++ testing is serious business and all that, but it's also
+a lot of fun. Let's keep it that way. Let's strive to be one of the
+friendliest communities in all of open source.
+
+As always, discuss Google Test in the official GoogleTest discussion group.
+You don't have to actually submit code in order to sign up. Your participation
+itself is a valuable contribution.
+
 ## Style
 
-Samples in this repository follow the [Google C++ Style Guide](
-https://google.github.io/styleguide/cppguide.html).
+To keep the source consistent, readable, diffable and easy to merge,
+we use a fairly rigid coding style, as defined by the [google-styleguide](https://github.com/google/styleguide) project.  All patches will be expected
+to conform to the style outlined [here](https://google.github.io/styleguide/cppguide.html).
+
+## Requirements for Contributors ###
+
+If you plan to contribute a patch, you need to build Google Test,
+Google Mock, and their own tests from a git checkout, which has
+further requirements:
+
+  * [Python](https://www.python.org/) v2.3 or newer (for running some of
+    the tests and re-generating certain source files from templates)
+  * [CMake](https://cmake.org/) v2.6.4 or newer
+  * [GNU Build System](https://en.wikipedia.org/wiki/GNU_Build_System)
+    including automake (>= 1.9), autoconf (>= 2.59), and
+    libtool / libtoolize.
+
+## Developing Google Test ##
+
+This section discusses how to make your own changes to Google Test.
+
+### Testing Google Test Itself ###
+
+To make sure your changes work as intended and don't break existing
+functionality, you'll want to compile and run Google Test's own tests.
+For that you can use CMake:
+
+    mkdir mybuild
+    cd mybuild
+    cmake -Dgtest_build_tests=ON ${GTEST_DIR}
+
+Make sure you have Python installed, as some of Google Test's tests
+are written in Python.  If the cmake command complains about not being
+able to find Python (`Could NOT find PythonInterp (missing:
+PYTHON_EXECUTABLE)`), try telling it explicitly where your Python
+executable can be found:
+
+    cmake -DPYTHON_EXECUTABLE=path/to/python -Dgtest_build_tests=ON ${GTEST_DIR}
+
+Next, you can build Google Test and all of its own tests.  On \*nix,
+this is usually done by 'make'.  To run the tests, do
+
+    make test
+
+All tests should pass.
+
+### Regenerating Source Files ##
+
+Some of Google Test's source files are generated from templates (not
+in the C++ sense) using a script.
+For example, the
+file include/gtest/internal/gtest-type-util.h.pump is used to generate
+gtest-type-util.h in the same directory.
+
+You don't need to worry about regenerating the source files
+unless you need to modify them.  You would then modify the
+corresponding `.pump` files and run the '[pump.py](googletest/scripts/pump.py)'
+generator script.  See the [Pump Manual](googletest/docs/PumpManual.md).
+
+## Developing Google Mock ###
+
+This section discusses how to make your own changes to Google Mock.
+
+#### Testing Google Mock Itself ####
+
+To make sure your changes work as intended and don't break existing
+functionality, you'll want to compile and run Google Test's own tests.
+For that you'll need Autotools.  First, make sure you have followed
+the instructions above to configure Google Mock.
+Then, create a build output directory and enter it.  Next,
+
+    ${GMOCK_DIR}/configure  # try --help for more info
+
+Once you have successfully configured Google Mock, the build steps are
+standard for GNU-style OSS packages.
+
+    make        # Standard makefile following GNU conventions
+    make check  # Builds and runs all tests - all should pass.
+
+Note that when building your project against Google Mock, you are building
+against Google Test as well.  There is no need to configure Google Test
+separately.