ShellExtensionSettingsPage: add simple preview for context menu items
Lock ByNameMap to make it thread safe.
Realigned code.
Merge branch 'master' into Portable
Minor spacing issue.
Merge branch 'master' into Portable

Conflicts:
	GitCommands/Settings.cs
Merge branch 'master' into Portable
Merge remote-tracking branch 'upstream/master' into Portable
Merge remote-tracking branch 'upstream/master' into Portable
Wireup event handlers.
Merge branch 'pr/n1808_vbjay'
Suggest prune branches if remote branch no longer exist
Make selected item visible.
RunningOnXXX methods moved to EnvUtils. It will allow to register NBug before Settings class is initialized.
Merge branch 'pr/n1661_feinstaub'