Add an 'About' section in the documentation

Add a new file `about.md` with a brief description of the plugin
that will be included at the top of the plugin's documentation
index.

Change-Id: I04670af6dbec0dffe6b21434dd3f8815d0eee9dd
1 file changed
tree: a428d2fb495e1999c90fe6a2a236ac8e9730f313
  1. src/
  2. .gitignore
  3. BUCK
  4. LICENSE
  5. pom.xml