Undo apparent accidental @-color replaces in upstream TBA files. (#62)

I am guessing some script or tool used upstream is doing an unsafe
search-and-replace for '@' with TAB, and accidentally changing these.
They seem to have been creeping into the repo for years.

I produced this fix commit automatically with:
  sed -i 's|\t\([bcdgmnoruwyBCDGMRWY]\)|@\1|g' tba/*/*.*
...and then a few files' changes had to be undone.

I looked through all of the rest, and they look like correct fixes.

I also ran all the other letters, and they only make incorrect "fixes".

lib/world/trg/0.trg

@@ -1568,7 +1568,7 @@ Eval and Set Example~
 2 d 100
 test~
 * By Rumble of The Builder Academy    tbamud.com 9091
-* This is a speech trig 	RHELP TRIGEDIT ROOM SPEECH	n, say 'test' to activate.
+* This is a speech trig @RHELP TRIGEDIT ROOM SPEECH@n, say 'test' to activate.
 * There is much confusion about the difference between set and eval. So this is
 * the simplest way I can think of to explain it (assume %actor.level% = 34):
 *