Patch Set 4: Looks good to me, approved; IP review completed

- rebased onto current master
- reformatted commit message and fixed some typos
- verified tests
- filed new bug https://bugs.eclipse.org/bugs/show_bug.cgi?id=319394 detected by failing GitCloneWizardTest.updatesParameterFieldsInImportDialogWhenURIIsUpdated (GitCloneWizardTest.java: 78)