rem old: DefaultHash, defList; add defaultlist
NEW: mei/__init__.py to Start MEI Development
WIP-MEI: patch converter.Converter.parseData() to detect MEI vs MusicXML
WIP-MEI: Add Basic Support for Importing <note> Tags

I have a bunch of functions, including tests, that should hopefully serve as a
model for how development will continue. So far, it's only for the <note> tag,
including only these attributes: accid, pname, oct, dur, and dots.
New: Add Support for <note xml:id="">

The xml:id attribute is now carried over into a Note object's "id" attribute.
Formatting: Moved mei/__main__.py Tests into mei/test_main.py

Music21 tests are usually kept in the same file as what they're testing, but
I've separated them here because:
- there will be a *lot* of tests
- it reduces (or "will reduce") the import footprint
- it makes cleaner files (for me)
- we can always put it back later