Fix dialog to select Git repository location
Previously the dialog had several bugs, this change:
- Prevents infinite loop if multiple repository mappings were found
- Removed break statement which prevents from inspecting upper levels
- Fixed logic to find any existing git repositories. It never
searched parent directories for a linked resource or project
itself due to an extra 'else' statement.
- Enabled repository creation if there is no '.git/' directory in
the project's root.
Bug: 291303
Change-Id: I47e8fd4a77083010cec880cd976d9e99a9e1ba5b
Signed-off-by: Mykola Nikishov <mn@mn.com.ua>