Added some start of contributing.

Author: joneshf

CONTRIBUTING.md

@@ -0,0 +1,14 @@
+# Contributing
+
+If you need to contribute to the old version, do that on the `0.3.x` branch.
+The main branch is for `0.4.x` and newer.
+
+1. When creating a new release, run one of the following:
+
+    * `gulp bump-patch`
+    * `gulp bump-minor`
+    * `gulp bump-major`
+
+    Depending on the changes.
+1. Run the following to create a tag: `gulp tag`.
+1. Push these both up to git with something like: `git push --tags`.