Bug fixes

Addressing bug in ViewController where the label & spinner get removed
every time a page request is made. Also, adding logic to the library
scraper so that it properly adds commas after each song entry (except
the last one).
Adding playlist scraping to project

Added code to MusiomeiTunesLibraryScraper for playlist scraping. Also
removed whitespace & newlines in JSON generation for ligher payloads.
Session ID fetch

Grabbing the current session ID from the 'musiome.sid' cookie. Storing
it to an ivar as well as to NSUserDefaults
Setting gitignore to all xcuserstate files