has_color() performance fixes

Performance profiling showed that multiple strcmpi() calls were
occurring each and every time a character was going to the map.

This update:
- honors the WC_COLOR capability
- It allows a window-port to control individual color availability should the window-port wish to do so.
- Makes checking on the individual colors for the active window-port is a straightforward table lookup at the CLR_ offset.

iflags.use_color remains a master on/off switch for use of color, regardless of the capability
compiled into the game (default TRUE).

The has_color() routine, which is now a shared routine in src/windows.c, could likely be made
into a simple macro to eliminate the function call, but this update does not go that far.

This hits a lot of port files due to the window-port interface change, mostly cookie-cutter.

src/mapglyph.c

@@ -245,16 +245,11 @@ unsigned mgflags;
 #ifdef TEXTCOLOR
     /* Turn off color if no color defined, or rogue level w/o PC graphics. */
     if (!has_color(color) || (Is_rogue_level(&u.uz) && !has_rogue_color))
-        color = NO_COLOR;
 #endif
-
+        color = NO_COLOR;
     *ochar = (int) ch;
     *ospecial = special;
-#ifdef TEXTCOLOR
     *ocolor = color;
-#else
-    nhUse(ocolor);
-#endif
     return idx;
 }