Spurious space.
Add support for full rests through center aligned tickables and custom durations
Fix auto-stem calculation, use same function for calculating beam group stem directions in .generateBeams() and autoStem on construction, fix TabNote bug where the stem direction was being always forced UP on construction, add/fix tests
Change integer stem directions to constants, swap incorrect test names for .dotsAndBeamsUp/Down
Merge pull request #253 from Silverwolf90/fix/auto-stemming

Fix auto-stem calculations
Added PauseMarking class
Add `Note.hasFixedYs()` and `PauseMarking.getFixedYs` to facilitate  special case by functionality instead of category
Fix indentation, add Stem direction constant