Add graphic assets for Google Drive
Add skeleton implementation files
Add Google Drive API dependencies
Implement linking to Google account
Able to instantiate a Drive service and authenticate
Implement GoogleDriveFileProvider.listFiles()
Implement GoogleDriveFileProvider.openInputStream();
Implement file ID caching for faster performance
Implement GoogleDriveFileProvider.isDirectory()
Fix modifiedDate in GoogleDriveFileProvider.fileToEncFSFileInfo()
Allow linking from VolumeListActivity
Show login toast
Use credential.getToken() in GoogleDriveAccount
Save Drive preferences and implement unlink
Auto login to Google Drive when application is created
Fix Google Drive icon aspect ratio
Implement GoogleDriveFileProvider.move()
Implement GoogleDriveFileProvider.mkdir()
Implement GoogleDriveFileProvider.delete()
Implement GoogleDriveFileProvider.copy()