Prepare track for implementing 3rd effect argument

This allows to slide the tremolo and vibrato values.
Add effect setter/getter to track

This functions can be used to use the new 3rd effect parameter which slides the
tremolo and vibrato values.
Add 3rd parameter to bliplay effect command

This uses the new effect setter from the track.
Add 3rd parameter to bliplay effect command

This uses the new effect setter from the track.
Merge branch 'develop' into 0.3.3

Conflicts:
	dev/bliplay/BKCompiler.c
Merge branch '0.3.3' of https://github.com/detomon/BlipKit into 0.3.3

Conflicts:
	dev/bliplay/BKCompiler.c
Empty uninitialized array

Trailing values were uninitialized and caused some side effects. Empty unused
values of array.
Bump version to 0.3.3