Remove transitions involving sequences

[cknadler]

After some thought, I think transitions to or from a sequence should result in a runtime error.

For example...

Standard transitions: (which are valid)

1:1 / 1:3

1:1 / 3

OpenG: (6:3 5,2,1:2 4,3:0)

OpenG / 1:2

Sequence transitions: (which should be invalid)

1:1 / [1:3 3:1]

[1:3 3:1] / 1:1

I'm invalidating these in the grammar for two major reasons:

• This is an edge case at best and is very confusing. It is difficult to tell if the transition applies (like an operator) to the sequence as a whole, or just to the first element (or something else entirely).
• It, alone, makes parsing much more complex.

[russplaysguitar]

Yeah, that sounds good

[cknadler]

This is done, tests still need to be written though.

[russplaysguitar]

Wrong order!

1) Tests 2) Code