Typo fix (:artist -> :artists)
Fix broken lines in LateJunction.tracks

First, replace all non-breaking spaces with spaces. Then, append lines
which begin with a forward slash to the preceding line, as they are
broken. For an example, see the 10:33 tracks at:
<http://www.bbc.co.uk/radio3/latejunction/pip/9eaog/>
More flexible track parsing

Allow a colon with any number of spaces after it, just in case.
Add Rakefile with spec task