Include injection grammars in active list

Prevents an immediate flicker when restarting Atom with editors
open that have injection matches.
Use getter on GrammarRegistry
Merge pull request #3458 from atom/ks-store-injection-grammars

Include injection grammars in active list
Prepare 0.126
Upgrade bracket matcher to use new apis

It was really noisy with deprecations
Upgrade to apm 0.92.1
:penguin: Add separator after preference items

Closes #3471
Upgrade to tree-view@0.115