Move the #value mapping from FieldOptions to FieldBase
Pass #title_display into the zendesk field
Merge pull request #6 from makangus/pass-value-and-title-display

Pass value and title display
Catch error from zendesk and throw exception
Merge pull request #7 from makangus/catch-zendesk-error

Catch error from zendesk and throw exception
Support #empty_option for select fields
Merge pull request #8 from makangus/8-support-empty-option

Support #empty_option