Added parsing for pianobar output to get info of the song currently playing.

- Added line parsing for pianobar output that shows the song, artist and album it is currently playing, under parser.py.
- Added a unit test for the parsing under parser.py. Modified pandora_parser.py to parse the lines and print the results.
- Added a gitignore file (currently ignores parser.pyc only)
Added downloader class to download the songs. Changed pandora_recorder so that the downloader will download every song that plays with pianobar.
Added downloader.pyc to .gitignore.