[NH5] Update src directory

[StephenOman]

This is a big set of changes so to break it down into the steps I followed:

1. Deleted file that doesn't exist anymore in NetHack5 mapglyph.c.
2. Overwrote all NetHack files that don't contain any NLE mods. This list was compiled by comparing NetHack 3.6.7 with NLE source files.
3. Overwrote NetHack files that contain NLE mods, one per commit to make review easier, restoring the NLE mod where appropriate. In some cases, the function being modified is now located in a different file, so the commit contains multi-file changes.
4. In a few instances, NetHack5 contains code that addresses issues NLE had. In this case, I've retained the NetHack5 version (e.g. issue Segfault in trap.c: Boulder goes out of bounds #98)
5. The macro-based function declaration style (FDECL) in previous NetHacks is gone. I've updated NLE code to match this style.

I've added a comment containing "NLE" before each change too for future reference. Hopefully I got them all.

[heiner]

very nice