Added two new options:

    * autocompleteMatchAnywhere
    * allowOnlyAutocompleteTags

Added examples of both settings
Changed how allowOnlyAutocompleteTags checks works.

Updated the valid tag check with the allowOnlyAutocompleteTags setting so that it works with availableTags and autocomplete.source (be it an array or callback).  Also added a couple more examples to show this working.
Merge https://github.com/amnuts/tag-it

Conflicts:
	examples.html
	js/tag-it.js