Merge pull request #398 from jtwigg/develop

Develop
Updates Help menu to link to correct documentation.
Merge branch 'develop' of github.com:apportable/SpriteBuilder into develop
update SB+SK to version without SK+Quicklook
update sb+sk with sound effects timeline playback
Merge pull request #409 from KoboldKit/develop-steffen

update SB+SK submodule with sound effect & callback timeline working
Merge pull request #412 from jtwigg/develop

mixup rest lengths to use localLength
Merge pull request #413 from jtwigg/develop

early exit various keyframe actions for joints.
Fixes delay when playing first sound
Merge branch 'develop' of github.com:apportable/SpriteBuilder into develop
Fixes #421
Merge branch 'develop' of https://github.com/apportable/SpriteBuilder into develop