feat(configuration): Add support for validation

Add support for custom validation so options can be validated when
they are loaded. If an option is deemed invalid, its default value
will be used instead (global first, local last).
feat(tagsInput): Add type option

Add a new 'type' option so the internal input element can customized.
Only a few values are currently supported: text, email and url. Due to
the use of the ti-bind-attrs directive, Angular will NOT process the
provided value and as a result of that no validation will be performed
whatsoever.

Closes #140.
chore(build): Update build files [skip ci]