edit CONTRIBUTING.md

Author: guillermooo

CONTRIBUTING.md

@@ -1,11 +1,31 @@
-Contributing
-============
+## Contributing
 
-There are two permanent brances: **master** and **dev**.
-**Master** always points to the latest release tag. 
-All development is done in **dev** branch, 
-please, use it for pull requests.
 
-If you are fixing grammar (syntax highlighting), please, add affected samples to [test-file.ps1](/tests/samples/test-file.ps1). 
-We use it in automated tests that compare grammar against PowerShell tokenizer.
-It also serves as a place for humans to stare to all exotic language constructions.
+Thanks for taking an insterest in contributing to the PowerShell package for
+Sublime Text 3!
+
+
+### Development
+
+Development happens on the **dev** branch. Please send your PRs against that
+branch only.
+
+
+#### Running Tests
+
+If you ara adding functionality or making substantial changes to existing
+code, please add tests and ensure that existing tests pass.
+
+Currently, we have very few tests and they aren't easy to run... :-(
+
+If you feel lazy about writing tests, this is the right time to contribute --
+we'll turn a blind eye more often now than later on! ;-)
+
+
+### Building Versions
+
+The easiest way to 'build' a version now consists in copying the top-folder's
+content to your *Data/Packages/PowerShell* directory.
+
+We have build scripts under *.\bin*, but they aren't realiable. We hope to fix 
+this soon.