Parse and test negative octaves. closes #144

[tp2750]

This fixes #144 : name_to_pitch fails for negative octave

It includes a test for a relevant set of pitches:

@test all([name_to_pitch(pitch_to_name(i)) == i for i in 0:88])

Before patch:

julia> join(name_to_pitch.([pitch_to_name(i)  for i in 0:24]), ", ")
"24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24"

With patch:

julia> join(name_to_pitch.([pitch_to_name(i)  for i in 0:24]), ", ")
"0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24"

[Datseris]

Thank you! Please increment patch version in Project.toml so I can merge and tag!

[tp2750]

Thanks a lot @Datseris . Version number updated to 2.0.1.