Add directories for UI and API classes.

Add directories for UI and API classes.
Add groups to the project.

Add groups to the project.
Merged with Vadim-branch.
Merge branch 'vadim'
Merge branch 'vadim'
Changes in the Redactor that should be in Vadim-branch.

Changes in the Redactor that should be in Vadim-branch.
Merge branch 'master' into vadim

Add some functions to the Metronome.

Conflicts:
	Rhythmus/Rhythmus/UI/MetronomeVC.m
	Rhythmus/Rhythmus/UI/SERedactorVC.m