Ruler: label showing again for X/Y coordinate.
Ruler position labels showing again.
Font brightened a tiny bit.
Minor positioning changes for ruler position labels.
Font changed to Lucida Grande.
Refactoring: Added constant for font name.
Removed obsolete import.
Merge pull request #397 from jtwigg/develop

Develop
tighten up inspector node references.
Merge pull request #396 from NickyWeber/bugfix/#393_rulers_not_showing

Bugfix: #393 rulers not showing
Fixes #393 rulers are now displayed correctly
show joints in consistent order.
Merge branch 'develop' of https://github.com/apportable/SpriteBuilder into develop