Basically, tagsinput was complete

- Limit by a number of tags.
- Limit by length of each tag.
- [Corrector] Correct the inputted tag before validate the tag.
- [Matcher] Validate the corrected tag before add to tag list.
- Support placeholder of tagsinput.
- Support to customize the template of the tags.
- Not to add the duplicated tags.
- Press twice BACKSPACE to remove the last tag first time, after that
only once.
- Class .tagsinput-invalid will be shown if [matcher] return false.