Update Handlebars Makefile to prep for Handlebars.js upgrade.
Update Handlebars metadata to not require "escape" and use utils.

The most recent release of Handlebars makes it so we no longer have to
re-implement the "handlebars-utils" module.
Import Handlebars.js @ 1.0.rc.2.
Update Handlebars test to ignore empty-string test.

The Handlebars.js project changed the meaning of `isEmpty()` to return
`true` for empty strings. Since we no longer re-implement the
"handlebars-utils.js" file, this ignores the one failing test.

https://github.com/wycats/handlebars.js/commit/5f56d6
Update Handlebars documentation for upgrade.
Add Handlebars test for arrays as context objects.
Merge branch 'handlebars-1.0.rc.2' into dev-3.x
Build Y.Handlebars @ 1.0.rc.2.