a real faux notation: 13 equal

I've used a simple variant of standard notation for 13 equal based on
the premise of an alternating 1:2^(8/13) and 1:2^(7/13) circle of
fifths... so from Gb to F# you'd have:

7 1 9 3 11 5 0 8 2 10 4 12 6

And as standard 12-tET deviations you'd have:

C
Db -8
D -15
Eb -23
E -31
F -38
F# -46
Gb +46
G +38
Ab +31
A +23
Bb +15
B +8

I've found this to be a very handy (simple, useful...) standard
notational borrowing for this very non-standard tuning, 13 equal.

--Dan Stearns