Add VagrantStatus

- Manage status of opened projects
Add methods to VagrantUtils

- hasVagrantfile(Project)
- getVagrantRoot(Project)
Synchronize vagrant status with VagrantStatus
Fix display name of StatusManagementTopComponent
Fix a bug that reload status doesn't work in the statusbar
Update README
Merge pull request #24 from junichi11/synchronize-status

Synchronize status