Update initial install message to call out availability of Gitter channel.
Update initial install message to call out availability of Gitter channel.

jmanuel1/GitSavvy,asfaltboy/GitSavvy,stoivo/GitSavvy,stoivo/GitSavvy,stoivo/GitSavvy,ddevlin/GitSavvy,divmain/GitSavvy,asfaltboy/GitSavvy,jmanuel1/GitSavvy,divmain/GitSavvy,ddevlin/GitSavvy,divmain/GitSavvy,ddevlin/GitSavvy,asfaltboy/GitSavvy