This module allows you to require that the content supplied for entity fields, node titles or taxonomy terms names will be unique if so configured in each field or title/name of the entity, allowin
Reset Date Field module provides the "Reset" button just next/below Date Field. On click on reset button date, date time, created date get rest with default empty.
Linked Entity Reference provides a new field type which has a combination of link and entity reference capabilities. It lets you relate an entity with an arbitrary URL.