non existant file in MANIFEST
Add single and create wrapper functions.

Kill find-wrapper, since find is implemented using either single or next,
and having proxies on both find+next would break if find would hit the
next-wrapper.
added test-case for writing into null relations
more failing tests
add access to the DBIx::Class::Objects object from the result-objects
Merge pull request #1 from lbalker/master

fixes and a test demonstrating a problem with nullable relations