9xx with values <=0x20 in tempo mode now sets the correct speed.
9xx with values >0x20 in either mode now is ignored.
Fxx with values from 01 to 0A in tempo mode now sets the primary
tempo like it's supposed to (via a lookup table). A similar bug in
the initial tempo was also fixed.
Fxx with values from 01 to 0A in BPM mode now set the BPM.
Fxx in BPM mode now respects the rows per beat value.
OctaMED has a weird bug when setting the BPM to 1 or 2 that is used
at the end of electrosound 64.med. A check for this has been added.
The initial speed and initial tempo are no longer divided by
GCD(initial speed, rows per beat) in BPM mode, fixing numerous bugs.
Added support for legacy 8-channel mode tempos.
Fixed a bug where patterns with fewer tracks than the total number
of tracks wouldn't be loaded correctly.
Fixes #17.