moved core functionality to Core.hpp
fixed glitch applying themes even when clicking "Cancel"
made plugin load immediately after IDA startup
added "notes" field to theme selection
added stylesheet constants for font properties
  -> fixes problems when font other than Consolas is picked
minor code cleanup
Merge branch 'master' into develop
added ida-default "skin"
moved IDASkins default skin from default to idaskins-dark
changed version from 1.2.0 to 1.3.0
minor stylesheet fix
migrated from qmake to cmake build system
added script building binaries for all supported IDA versions
fixed linux build
finishing touch for 1.3.0 release