(emp_obj_chr_name): New. Returns a pointer to the characteristics name
for an empobj.
(unit_map): Simplify unit_map() by using get_empobjp() and
emp_obj_chr_name().
(map, cmd_move_map): Switch to EF_SHIP as unit_map does not default
to EF_SHIP for EF_BAD anymore.
(map): Call new function do_map().
(display_region_map): Modify to use do_map() instead of map().
(tran_nmap, tran_pmap, cmd_move_map): Modify to accomodate
the modified display_region_map() function.
other. Ensure headers in include/ can be included in any order
(except for econfig-spec.h, which is special). New header types.h to
help avoid inclusion cycles. Sort include directives. Remove some
superflous includes.
Modify nmap command to allow mapping around a nuke.
Add new command nbmap for bmapping around a nuke.
Add a new mapping flag 'n' for adding nukes to a map.
Correct syntax description for pmap, pbmap, lmap and lbmap
in player_coms[].
silly EF_NMAP. Use characters instead: 'b' for bmap (was EF_BMAP),
't' for true bmap (was EF_MAP), 'r' for revert (was EF_MAP+EF_BMAP,
more sillness), and 'n' for nmap (was EF_NMAP). Callers changed.
(EF_NMAP): Remove.
