Announce 2014-08 VM udpates

Announcement is tentatively set to 20th of August.
Announce move to Leiningen 2.x
Fix grammar

Thanks, @GrahamCampbell!
Add the definite article
Reformat updates and single out Firefox in a separate header
Various updates
Add anticipated PHP updates
Make the switch in Leiningen's default clearer
Update GHC tools
Document MongoDB PPA change
Document upcoming ElasticSearch update
Mention Android build-tools
Change publication date
Rework introduction
Change update schedule
Move Leiningen default change
Rearrange sections to be alphabetized

Also remove mention of nvm
Various tweaks based on feedback
Add notes about Gradle 2.0
Remove distracting dashes from the post