Added Rick Osborne's super-easy gitflow installer oneliner to the project.

See the README file for instructions on how to use it.
diff --git a/AUTHORS b/AUTHORS
index c764de4..b54d16b 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -5,5 +5,6 @@
 - Daniel Truemper
 - Jason L. Shiffer
 - Randy Merrill
+- Rick Osborne
 
 Portions derived from other open source works are clearly marked.