Bug fixes and change episode renaming format

Fixed the regular expression for renaming shows and episodes to allow
hyphens. fixFileName's second argument now determines if semicolons
should be replaced by underscores. The new naming format is: if an
episode does not have a proper title then append the start date as
mm_dd_yyyy. If that filename already exists then append the time as
hh_mm_ss. So a file could end up being named: Show -
05_07_2014-10_59_00.