fixes3-7-0.txt entry: WASM pull request 1331

The pull request was:
    https://github.com/NetHack/NetHack/pull/1331
by @guillaumebrunerie

The text by @guillaumebrunerie that accompanied the pull request was:

I have been working on a browser/mobile port of NetHack 3.7 using
cross-compilation to WebAssembly (it is very playable already, you can
try it at https://guillaumebrunerie.github.io/nethack/).

[screen shot]

The existing code for compiling to WebAssembly was a great help, although
it wasn't fully up to date and was missing a number of things in order
to be able to create a proper window port (for instance there was no way
to set 'iflags.window_inited' to true, 'print_glyph' was not working
properly as its signature changed, and various other things).

This pull request contains various fixes and additions that I found were
needed/helpful.

Changes:

 * export more constants/pointers/globals.
 * fix various types that are incorrect.
 * disable compression of save files, as it uses fork which isn't supported
   in WebAssembly.
 * include 'genl_player_setup' when 'SHIM_GRAPHICS' is defined, in order to
   make it possible to reuse the existing player selection code.
 * move initialization of JavaScript global constants up, as I was running
   in some issue when 'raw_print' was being called before initialization.
 * change various compilation options for Emscripten, in particular it now
   generates an ES6 module (easier to use in a modern Javascript project)
   and exports more methods from Emscripten (for instance to be able to use
   the virtual file system when saving).
 * simplify the implementation of the main loop to avoid 'setTimeout' which
   can be pretty slow in the browser when called many times.
 * change the way pointer arguments are being sent to JavaScript in 'getArg'
   (they were being sent as a pointer to the pointer itself on the stack,
   which doesn't really make sense, now the pointer itself is sent).

doc/fixes3-7-0.txt

@@ -2922,6 +2922,8 @@ split "cannot_push" on moverock_done() into a separate function (pr #1282
 	by argrath)
 split making pits on do_earthquake() into a separate function and
 	eliminate some gotos on do_earthquake() (pr #1287 by argrath)
+update the WASM cross-compile to work with the current
+	code (pr #1331 by guillaumebrunerie)
 
 
 Code Cleanup and Reorganization