Fixes #29464 - plain inputs can be hidden

Some inputs can be sensitive. Users typing such values would prefer to
have the value hidden in the form. The sensitive information can be a
password, private key or general multiline text. Therefore we aren't
limitting the input to type=password, but use text area with hiding...

Fixes #11367 - Default values for the template inputs

Fixes #27662 - template inputs - adding field

Fixes #26080 - Add autocomplete and date to report template (#6531)

Fixes #25102 - introduce template inputs

This adds the formal template inputs to all templates. It's heavily
based on current implementation from remote execution plugin.