Merge pull request #45 from vosen/fix-43

Handle non-mod pub keyword usages in module parser
Merge pull request #46 from vosen/fix-43

Add EnvDTE reference to project subproject
Merge pull request #47 from vosen/master

Fix some bugs, improve module tracking
Sync grammar with the upstream

Fixes #44
Merge branch 'master' of https://github.com/PistonDevelopers/VisualRust