Categories with Empty Titles / Duplicate Error

[ciur]

Description

Two problems here.

1. It is possible to create category with empty title
2. Once there is a duplicate title - the error message is not very user friendly

Acceptance criteria:

1. Categories with empty should not be allowed
2. Display user friendly message when category with same title already exists e.g. "category with this title already exists"

Info:

• Version 3.5