Adjusted whitespace.
Renamed loadSoundFont to load_sound_font.
Adjusted docstrings and whitespace.
Reformatted diagnostic print() messages.
Reformatted long lines.
Reformatted long lines.
Expanded abbreviations in variable names.
Cleaned up Python 2/3 compatibility.
Clarified variable names.
Extracted OGG and MP3 rendering and display into separate functions.
Integrated render-success checks.
Alphabetized functions.
Cleaned up module.
Refactored play() functionality as a callable `Play` class.

This makes the use of the `global` keyword unncessary, as the midi bank and
sound font can be cached as instance properties on the class rather than as
module-level globals.
Added .gitignore.
Improved path handling.
Merge pull request #1 from josiah-wolf-oberholtzer/master

Prepared abjad-ipy-midi for integration into Abjad mainline