Also remove trailing whitespaces from the file

Fixes #3125

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.

Before, android versionName was set to "...13", which made the f-droid build fail.

The service isn't online, and on the long term, mmdb will likekly be
replaced with other services from the modding community.

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).