small grunt fixes

The grunt-generated banner makes it unnecessary to include license.txt.

(Before this change, the non-minified file has essentially the same
banner twice.)

Change craftyengine.com to craftyjs.com, which seems to be the canonical
address.
Merge pull request #527 from sbyrnes321/develop

small grunt fixes
Customizable game loop

This patch reworks the game loop to allow control over its behavior.  It can now be set to three modes, which control what dt is passed to each frame, as well as how often frames are called.

* "fixed", which is the existing behavior.  Each frame processes the same amount of time, and as many frames as necessary are processed to reach the target rate.
* "variable", which processes a single frame per render.  This frame is handed the total time since the last frame, up to some maximum value.
* "semifixed", which takes the total time since the last step, and splits it evenly between as many frames are necessary to avoid exceeding some maximum timestep.

It also cleans up how the game loop and Crafty.timer are actually implemented, moving a bunch of internal variables into the scope of Crafty.timer.
Merge pull request #528 from starwed/step-control

Customizable game loop
grunt should create API directory if it doesn't already exist

Fixes issue #532
Merge pull request #533 from sbyrnes321/develop

grunt should create API directory if it doesn't already exist
Removed dead links from README.md
Fixed #534 making the api template use jekyll template
refactor .requires, documentation for .requires and .addComponent

Now that addComponent does not re-add components that are already added,
it has become exactly the same as requires. Therefore I deleted the
redundant code and clarified the documentation.
edit requires documentation
Update core.js

Improve the condition to triple equal.
Merge pull request #537 from matheusazzi/patch-1

Update core.js
Fixing timing test based on game loop refactor.
Merge pull request #535 from sbyrnes321/develop

refactor .requires, documentation for .requires and .addComponent
Merge pull request #538 from ericathegreat/stage-testfix

Fixing timing test based on game loop refactor.
Create .travis.yml Fixed #540
Updated package.json with the default test script
Make Color and Sprite components work together for DOM elements
Merge pull request #542 from zipang/develop

Fix: Make Color and Sprite components work together for DOM elements