Core: New method FacilityManager.bl.addHosts.

Core:
- New method addHost take host names as list of string and if there is a pattern made of square
brackets (e.g. "name[00-12]domain") it generates new host names and
then call old method addHosts, so all hosts are created. The logic is written in the class impl.Utils.
- New created exception WrongPatternException thrown when generative
  hostname has a wrong syntax.
RPC:
- Now when addHosts is called from RPC, the generation of host names
is enabled.