Change of version number in preparation for the update
Added TODO comments to the code

The TODO-s signal what should be done to update to the new version. Most of it is simplification, except for ``@itemprop-inverse`` that means duplicating some code. I have not yet checked whether the duplication can be simplified by factoring out some parts (and it is not sure that this is worth the trouble).
Made all the necessary changes; next step is testing
Added a -v flag to the local script, good for debugging
Doh. Stupid error in the previous step:-(
Created a rudimentary test runner
First run through the test suite, found the ones which do not seem to work properly

These are: #51, #67, #75-77
Took care of errors 75-77

The <data> element should not appear with @src, which was the case (also in the earlier version, b.t.w.)
Took care of error 51

An extra mapping from items to blank nodes is necessary, to ensure the unicity of bnodes
Regenerated the documentation
Handling of itemid was incomplete (relative URI-s were not handled)
Ran the code through the pyCharm code inspection (just minor issues)
Final regeneration of the documentation
First step for itemprop-reverse: slight reorganization of the triple generation part
itemprop-reverse implemented (and documented)
Debug flag set to False
Significantly reduced the number of predefined vocabulary bindings. With the schema-centric usage, this is really not useful for microdata...
cosmetic changes on the code