Fix indentation for 'Move class to File' function

'Move class to File' function did always use tab as indentation
character. As space user you always had to convert the tabs to spaces by
hand afterwards. This fix tries to find and set the right indentation
character. If no indentation character is found, it falls back to tab.
Added CSharpFormattingOptionsContainer as preparation for policy-based formatting options and serialization.
Created prototype of formatting options editor.
Merge pull request #366 from sven-n/fix-move-class

Fix indentation for 'Move class to File' function
PackageManagement: Solution-level Packages

Support for Solution-level Packages
PackageManagement: Events, Exceptions, Refactoring
PackageManagement: OnPackageManaged
PackageManagement: Solution-level Packages Fix

IsPackageInstalled added support for solution-level package
PackageManagement: Fix name, remove obsolete code
PackageManagement: OK, need better refresh
PackageManagement: Refresh AvailablePackages
PackageManagement: cleanup
PackageManagement: cleanup again

Remove obsolete argument
PackageManagement: More cleanup
PackageManagement: Comply with test expectations
Showing appropriate selections for option values now functional.
PackageManagement: notes
Backup
PackageManagement: Tests OK
PackageManagement: Fix refresh