added gitk
Merge branch 'master' into macbookair

* master:
  fix heading
  fix references to R
Merge branch 'master' into macbookair

* master:
  list remote branches
added maven command line options
clean up page
Merge branch 'master' into macbookair

* master:
  added maven command line options

Conflicts:
	pages/frank/maven/command_line.txt