Analogue-sequencer

Folks,

I've uploaded another beta firmware update.
This extends the direction options a bit.

The previous 'pendulum' behaviour has been renamed 'alternate'.
The revised 'pendulum' mode now plays back and forth (or should that 
be forth and back ?) without repeating the end steps.
Note that this mode interacts differently with gbar 
than 'alternate', so unless you have chg=p, a penduluming pattern 
with a length the same as gbar may not seem to pendulum. 

Also added is an extra reverse mode - there are now 'reverse A' 
and 'reverse B'. The difference being that the first starts at the 
first non-skipped step in the pattern, and the second starts at the 
last non-skipped step. This makes a difference to the rhythmic 
interaction between the reversed pattern and the other tracks.

I'm still thinking about the random modes, but have come up with a 
bit of a quandry as to how they should behave.
If a pattern is playing randomly, how may steps should it play 
before the playlist advances ? I was thinking of playing random 
steps for the 'length' of the pattern, or should it be the number of 
non-skipped steps before the last... ? 
I was also thinking maybe the 'length' value is redundant since I 
added skip... 

Cheers,
Colin f