Fixed some warnings in validate_legacy_program
Laid new file rename structure in window.c to be filled in at a later date.  Alt+R will now do nothing.
Merge branch 'master' of git://github.com/ajs1984/megazeux
Fixed string allocation on setting $string.length
Added bounds check to INC "$string" "value".
Fixed crash where increasing a string by itself would cause crashes if the reallocated pointer of the string was more than MAX_INT bytes away from the original pointer.
(Mr_Alert) Rolled string->storage_space's funtionality into string->name
Fixed crash when attempting to reload the current board module after failed validation when leaving the editor.
Changelog modification
Fixed bug where COPY BLOCK $string would prefix the coordinates twice.
The mzx_world version is now passed down to boards and robots and is handled separately from the file version in load_*_allocate
String max length is now 4MB
Fixed bug where storageless types couldn't be edited with ALT+M if a non-storageless type was in the buffer.
Lengthened the export filename array in robo_ed to MAX_PATH
Fixed ! operator so it works the same as ~, like pre-2.84 MZX, instead of invalidating the entire expression.
Fixed bug where setting an index that would increase the size of the string was increasing it too much.
Switching to and from overlay mode resets draw_mode now.
Changelog entry for previous commit.
ALT+M now edits the overlay instead of the board in overlay edit mode
Quick-load won't work during gameplay anymore if LOAD_MENU has been set to 0