Fix/migration forms v3

[TDannhauer]

Drop deprecated ->type access on form variables (V3 migration)

Summary

Horde\Form\V3\BaseVariable::__get('type') emits a WARN-level deprecation
("Variable property 'type' is deprecated, please remove '->type'") on every
access, because in V3 the variable IS its own type. With Turba (and any other
app rendering V3 variables) this floods the Horde log with dozens of warnings
per page render.

[amulet1]

I added this deprecation message specifically for that reason - to alert about no longer needed ->type (and few other things).

We just have to be careful - we can not remove it from places which still may utilize mixture of old classes (e.g. classes that extend Horde_Form_Type) and new V3 classes. Ideally we have to first migrate any apps relying on Horde_Form_Type to V3-compatible classes.

[amulet1]

As long as ->type is dropped only for V3 types (which is the case here as far as I can see), we should be fine.

[amulet1]

Also see horde/Form/pull/24.