Regression on pull request #395 modifications

There is a source code modification between https://github.com/davidstutz/bootstrap-multiselect/blob/744aa223767b5b5a474befdbcbdc9f4a412211a0/js/bootstrap-multiselect.js#L764 and https://github.com/davidstutz/bootstrap-multiselect/blob/a6699f2223ea8c986eb47a73f365eec503e5705a/dist/js/bootstrap-multiselect.js#L769 that makes pull request #395 ineffective.
