Converted song parts from String to enum
Separating dictionary into song parts
Refactoring Driver with methods
New test for song parts
Renamed Song to SongSegment
Re-adding duration (fixed) and tempo variable
Upgraded to latest JFugue
Added missing comments, few minor naming tweaks
New Song class with segments and key
Migrated key and relative major from SongSegment to Song
Removed unnecessary mode from SongSegment
Removed title and artist from SongSegment
Removed beats from SongSegment
Modified Driver to build complete songs
Changed buildProgression to accept sequence of Chords
Moved SongPart determination to XMLReader instead of SongSegment

Allowed for SongSegment to maintain only the dictionary pertaining to
its relevant SongPart
Moved SongSegment progression generation from Driver to SongSegment
Refactoring to have Songs build their segments
Tidied up toString methods, adding optional song part
Corrected bug in segment generation