Settings Hosts enum

[iLLiCiTiT]

Description

We use host names in filtering a lot but we don't have enumeration of available hosts in settings.

Changes

• added hosts-enum entity type which is enumerator with all possible host names
• has single selection and multiselection option
• it is possible to have empty value with custom label which is stored as empty string ""
  • to have this set use_empty_value to true/false
• entity can have defined custom_labels as dictionary where key is host name and valid is label
• replaced list of strings in hosts usage with new enum item

[jakubjezek001]

works perfect