Added a more comprehensive is_map test to HiPE.
Add has_map_fields test to the HiPE suite

Also cleaned up hipe_beam_to_icode slightly.
Merge branch 'hipe-maps-has-map-fields' into hipe-maps

Added HiPE support for the has_map_fields BEAM instruction.
Implemented get_map_elements in HiPE

Just a simple copy-and-paste if the has_map_fields implementation, but
with an additional
     Vali := maps:get/2(...)
ICode instruction added per key-value pair.

Changed the maps_guard_fun in maps_SUITE to accept the HiPE trace
format.