Commit

e4bff8be - Clean up threading

by @ShadowNinja has broken the OSX build.

Including things inside a namespace isn't good.

Also fixes #3124.

Before, calling get_areas_in_area for an areastore with both
include_borders and include_data would result in a lua error,
if there was at least one area as result:
attempt to index a number value in function 'get_areas_in_area'

Also remove trailing whitespaces from the file

Fixes minetest.get_player_information segfault due
to out of bounds access problems, when compiled as debug build.

The commit
8f9af573 "Add core.get_dir_list" by @ShadowNinja
has removed the implementation of the l_get_dirlist function and all its usages
from the l_mainmenu.cpp file, but hasn't removed it from the header file.

The reason why this hasn't been detected earlier is that C++ has this interesting
feature to still make it possible to create instances of classes whose never used
private methods are declared but not defined.

Preserves the rare unbroken protruding dungeons
Fix random range for first room roomplace
Fix checked volume for first room 'fits' bool
and check for 'untouchable' flag instead of 'inside'
Remove 'enable floating dungeons' setting

Fixes "double fault" / "error in error handling" messages
(issue #1423) and instead shows a complete backtrace.

  * Rename everything.
    * Strip J prefix.
    * Change UpperCamelCase functions to lowerCamelCase.
  * Remove global (!) semaphore count mutex on OSX.
  * Remove semaphore count getter (unused, unsafe, depended on internal
    API functions on Windows, and used a hack on OSX).
  * Add `Atomic<type>`.
  * Make `Thread` handle thread names.
  * Add support for C++11 multi-threading.
  * Combine pthread and win32 sources.
  * Remove `ThreadStarted` (unused, unneeded).
  * Move some includes from the headers to the sources.
  * Move all of `Event` into its header (allows inlining with no new includes).
  * Make `Event` use `Semaphore` (except on Windows).
  * Move some porting functions into `Thread`.
  * Integrate logging with `Thread`.
  * Add threading test.

This bypass had to be re-enabled as some users reported issues,
even after the iconv build fix.

While utf8_to_wide works well, wide_to_utf8 is quite broken
on android, for some reason, and some devices (unrelated from build
configuration).

Before, this lua code led to a crash:

local pcg = PcgRandom(42)
local value = pcg:next()

This was because if you called s32 PcgRandom::range(min, max) with the
minimum and maximum possible values for s32 integers (which the lua
binding code did), u32 PcgRandom::range(bound) got called with 0 as the
bound. The bound however is one above the maximum value, so 0 is a "special"
value to pass to this function. This commit fixes the lua crash by
assigning the RNG's full range to the bound 0, which is also fits to the
"maximum is bound - 1" principle, as (u32)-1 is the maximum value in the
u32 range.

Also misc. minor cleanups