Add tests for concatting Note and Rest to NoteSeq
Add tests for concatting Note and Rest to NoteSeq

Tests cover both forward and reverse adding

Signed-off-by: Adam Obeng <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@binaryeagle.com>

kroger/pyknon,palmerev/pyknon