Switch to YUIDoc for API docs.

Squashed commit of the following:

commit f6e539f1055431be2f4cb93984c5136ebb556dad
Author: Jeremy Kahn <jeremyckahn@gmail.com>
Date:   Tue Nov 11 20:51:06 2014 -0600

    Package up 1.3.6.

commit b4b63fbc0271fd8c39f3772c2bdc064000e1d1a2
Merge: 525c765 b0ed17b
Author: Jeremy Kahn <jeremyckahn@gmail.com>
Date:   Tue Nov 11 20:33:17 2014 -0600

    Merge branch 'master' into feature/yuidoc

commit 525c765ef5887575137ea99a7e0bb4f9912f76e2
Author: Jeremy Kahn <jeremyckahn@gmail.com>
Date:   Sun Nov 9 10:59:17 2014 -0600

    Improve token docs.

commit 6d104704ab8d03bd10b8ead0be9aef8f8a0237ff
Author: Jeremy Kahn <jeremyckahn@gmail.com>
Date:   Sun Nov 9 10:36:11 2014 -0600

    Reconfigure how docs are generated.

commit 5ade61bba497f5654a7092f48649902b160a7f60
Author: Jeremy Kahn <jeremyckahn@gmail.com>
Date:   Tue Nov 4 21:06:15 2014 -0600

    Wires up yuidoc and updates shifty.core.js annotations.