GUI: fix editable combo boxes
GUI: fix parsing of the RA action units
GUI: fix operation default value checking
GUI: disable "apply grp" button if there are not services

bug introduced in 1.5.14
GUI: fix units in CRM view
GUI: fix drbd view
GUI: fix drbd view units
junit: add level 0 unit tests
GUI: fix VM view
GUI: fix operation "same as" combo box
GUI: fix colocation npe
GUI: fix adding of DRBD resource agent
GUI: fix equal function in CRM view
GUI: increase width of the ip combo box in host wizard
GUI: fix host configuration wizard
GUI: fix host installation wizard