Iterator: start at begin, not end
Fix display of items on ground:

remove the special handling for the first item there, the loop below that will do it instead.
also reuse a variable (by_charges) instead of calling the function again.
Fix input involving the Alt keys in SDL:

Ignore a key only when it was added to the alt_down input buffer, otherwise forward the key as normal.
Some characters are entered with the AltGr key, which triggers the input of Unicode characters by number.
Note that SDL_Event::text::text contains the character that was entered by the user (e.g. '@'), not the keys that the user actually pressed.
add_alt_code can't handle '@' and returns false, which will forward the entered '@' to the game.
Fix sign comparison warning ins sdltiles.cpp

Make delaydpad and dpad_delay unsigned as they are used with SDL_GetTicks, which returns an unsigned value (Uint32).
Fix typo'd mod name

Seen two different misinterpretations of this one.  Gagh.
Fix disassembly bogus check, resulting in bogus results, memory sweeping and segfaults
Fix mistake allowing to use welder for unwelding
Merge remote-tracking branches 'dda/pr/8087', 'dda/pr/8091', 'dda/pr/8093' and 'dda/pr/8095' into dda-master

* dda/pr/8087:
  Fix display of items on ground:
  Iterator: start at begin, not end

* dda/pr/8091:
  Fix sign comparison warning ins sdltiles.cpp
  Fix input involving the Alt keys in SDL:

* dda/pr/8093:
  Fix typo'd mod name

* dda/pr/8095:
  Fix mistake allowing to use welder for unwelding
  Fix disassembly bogus check, resulting in bogus results, memory sweeping and segfaults
Little restyle and cleanup.