Update CONTRIBUTING and PROJECTS

This updates CONTRIBUTING to reflect the changes to use the
master branch and make explicit recommendations about updating
CHANGELOG.md and providing test coverage.  Also, this includes
some old updates to PROJECTS.md that I wrote to expand the list
of projects, pulling in things from old feature requests.

1 files changed, 40 insertions, 24 deletions

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 4efe28ed3..1444596d2 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -22,17 +22,25 @@ Also, feel free to open an
 about any concerns you have.  We like to use Issues for that so there is an
 easily accessible permanent record of the conversation.
 
+## Libgit2 Versions
+
+The `master` branch is the main branch where development happens.
+Releases are tagged
+(e.g. [v0.21.0](https://github.com/libgit2/libgit2/releases/tag/v0.21.0)
+and when a critical bug fix needs to be backported, it will be done on a
+`<tag>-maint` maintenance branch.
+
 ## Reporting Bugs
 
 First, know which version of libgit2 your problem is in and include it in
 your bug report.  This can either be a tag (e.g.
-[v0.17.0](https://github.com/libgit2/libgit2/tree/v0.17.0) ) or a commit
-SHA (e.g.
+[v0.17.0](https://github.com/libgit2/libgit2/releases/tag/v0.17.0) ) or a
+commit SHA (e.g.
 [01be7863](https://github.com/libgit2/libgit2/commit/01be786319238fd6507a08316d1c265c1a89407f)
-).  Using [`git describe`](http://git-scm.com/docs/git-describe) is a great
-way to tell us what version you're working with.
+).  Using [`git describe`](http://git-scm.com/docs/git-describe) is a
+great way to tell us what version you're working with.
 
-If you're not running against the latest `development` branch version,
+If you're not running against the latest `master` branch version,
 please compile and test against that to avoid re-reporting an issue that's
 already been fixed.
 
@@ -44,25 +52,33 @@ out a way to help you.
 
 ## Pull Requests
 
-Our work flow is a typical GitHub flow, where contributors fork the
-[libgit2 repository](https://github.com/libgit2/libgit2), make their changes
-on branch, and submit a
-[Pull Request](https://help.github.com/articles/using-pull-requests)
-(a.k.a. "PR").
+Our work flow is a [typical GitHub flow](https://guides.github.com/introduction/flow/index.html),
+where contributors fork the [libgit2 repository](https://github.com/libgit2/libgit2),
+make their changes on branch, and submit a
+[Pull Request](https://help.github.com/articles/using-pull-requests) (a.k.a. "PR").
+Pull requests should usually be targeted at the `master` branch.
 
 Life will be a lot easier for you (and us) if you follow this pattern
-(i.e. fork, named branch, submit PR).  If you use your fork's `development`
-branch, things can get messy.
+(i.e. fork, named branch, submit PR).  If you use your fork's `master`
+branch directly, things can get messy.
+
+Please include a nice description of your changes when you submit your PR;
+if we have to read the whole diff to figure out why you're contributing
+in the first place, you're less likely to get feedback and have your change
+merged in.
+
+If you are starting to work on a particular area, feel free to submit a PR
+that highlights your work in progress (and note in the PR title that it's
+not ready to merge). These early PRs are welcome and will help in getting
+visibility for your fix, allow others to comment early on the changes and
+also let others know that you are currently working on something.
 
-Please include a nice description of your changes with your PR; if we have
-to read the whole diff to figure out why you're contributing in the first
-place, you're less likely to get feedback and have your change merged in.
+Before wrapping up a PR, you should be sure to:
 
-If you are working on a particular area then feel free to submit a PR that
-highlights your work in progress (and flag in the PR title that it's not
-ready to merge). This will help in getting visibility for your fix, allow
-others to comment early on the changes and also let others know that you
-are currently working on something.
+* Write tests to cover any functional changes (ideally tests that would
+  have failed before the PR and now pass)
+* Update documentation for any changed public APIs
+* Add to the [`CHANGELOG.md`](CHANGELOG.md) file describing any major changes
 
 ## Porting Code From Other Open-Source Projects
 
@@ -80,10 +96,10 @@ you're porting code *from* to see what you need to do.  As a general rule,
 MIT and BSD (3-clause) licenses are typically no problem.  Apache 2.0
 license typically doesn't work due to GPL incompatibility.
 
-If you are pulling in code from core Git, another project or code you've
-pulled from a forum / Stack Overflow then please flag this in your PR and
-also make sure you've given proper credit to the original author in the
-code snippet.
+If your pull request uses code from core Git, another project, or code
+from a forum / Stack Overflow, then *please* flag this in your PR and make
+sure you've given proper credit to the original author in the code
+snippet.
 
 ## Style Guide