add current (broken) version of xwalk unit test.  Can't continue with testing xwalks until we resolve the issue of how notes are handled
fix note handling in xwalks and formcontext - notes are no xwalked in a totally straightforward manner, and the formcontext is responsible for maintaining old note dates and keeping or deleting existing notes.  A method _merge_notes_forward has been added which will handle this for all applicaiton forms