Update the readme with info about branch-master.xml

Reformat some of the chapters so they don't span multiple
lines in a normal editor.

Change-Id: I1f7365899632eadb74c11b48b30cd6d44b7d7f1a
Reviewed-on: http://review.couchbase.org/35457
Reviewed-by: Matt Ingenthron <matt@couchbase.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>