Tweaked RESOURCES.md
Tweaked RESOURCES.md

Formatted Stack Overflow with a space in between.
Capitalized Java in the Reddit link and removed the claim that it was official.
Removed Gitter room link
The documentation is official
exercism/xjava,FridaTveit/xjava,FridaTveit/xjava,jmluy/xjava,jmluy/xjava,exercism/xjava