Min-length="0" is not working as expected

[deje1011]

Hi there, Thank you for developing this component! I tried using ngTagsInput to select items with a property called "displayString". This property may be empty, so my template provides a default value: {{::data.displayString || 'No name'}

Those items are displayed inside the autocomplete list but cannot be selected, even though min-length is set to 0 and allowed-tags-pattern is set to .*. So I had a look in the source code and saw that it will never accept empty strings: https://github.com/mbenford/ngTagsInput/blob/87d0e6b695fd53d21f73357a1d3377ab569a78d0/src/tags-input.js#L69

Would it be possible to remove that check? Thanks a lot, Jesse