Update tern and acorn
Fixes a number of codehinting issues:
issue #3917
issue #3883
issue #3837
issue #3830
issue #3786
Merge pull request #4122 from eztierney/update-tern

Update tern and acorn
Merge branch 'master' of https://github.com/adobe/brackets into larz/framework-update-fixes
Font size tweaks to match Topcoat.