FormCheckoutBranch behavior fixed again when called from commit dialog

Conflicts:
	GitUI/CommandsDialogs/FormCheckoutBranch.cs
Merge remote-tracking branch 'gitextensions-pombeiro/BuildServerIntegration-plugin' into BuildServerIntegration-plugin
Merge remote-tracking branch 'gitextensions/master' into BuildServerIntegration-plugin
Merge remote-tracking branch 'gitextensions/master' into BackgroundFetchPlugin
Merge branch 'BuildServerIntegration-plugin' into all
Merge branch 'BackgroundFetchPlugin' into all