Adding a new Canvace.Timing module which provides abstraction of the timing APIs provided by the browser.

It currently provides a static Canvace.Timing.now() method, which wraps around window.performance.now() where available, or Date.now() otherwise.
Fixing a bug which occurred with the latest version of Firefox.
Some browsers don't have window.performance at all.
Code style.
Lint.
Browser API may use this.
Sketching the docs for Canvace.Timing.
Lint.
Merge branch '130115-timing' into 130115-physics