level: move decoder level logic to level.cpp, make table based

the new function enforces more limits defined in Annex A -
  widths and heights are capped to avoid extreme rectangular dimensions
  DPB size is limited based on resolution
  at higher resolutions, the min CTU size is 32

this commit also lays the groundwork for adding --level 5.1 --tier HIGH params
rc: update the default build output filename for our DLL