Renamed variable in foundation.forms.js

Changed reserved word 'char' to 'character' in order not to crash the google closure compiler.

As you can see here https://github.com/millermedeiros/amd-utils/issues/48 and here https://github.com/zurb/foundation/commit/b908b6d7f9be3696a2e06e74b21f9de2581ab5c0.

Regards.