If the player is disconnected while Lua API is doing a l_punch call, for example, the playersao is NULL and the server crash. Fix it.

Don't reinvent freetype detection, use working one from cmake.

This fixes a segfault when the database is shut down
before it finishes connecting and setting up.

Remove large cave checks for air
Mgv5/mgv7:Add is_ground_content checks to 3d noise tunnels
More large caves
Shorten lines

Fixes #2603

Also set the packet size at creation not when pushing rawString, no functional change

This greatly increases crafting performance, especially in worlds with many mods.

Approved by @kwolekr.

Introduces a hash-type-layered fall-through mechanism, where every layer specifies one hash algorithm,
and the "deeper the fall", the more collisions to expect for the algorithm. One Craft definition
only resides at one layer, which improves speed for lower layers (and a complete fail), due to most
craft definitions residing at high layers.

Due to the fall-through design, the undocumented behaviour that later craft recipes
override older ones had to be weaked up a bit, but craft recipes with the same hash and layer
will still override.

This seems to be a debug message which has been forgotten to be removed.

Approved by: @kwoelkr

Create PacketError exception and use it with ACTIVEOBJECT_REMOVE_ADD handler which can be unreliable

Speed-optimise leaves blits
Use MMVManip for make_jungletree
Use correct code style

Move debug streams to log.cpp|h

Move GUI-related globals to clientlauncher

Move g_settings and g_settings_path to settings.cpp|h

Move g_menuclouds to clouds.cpp|h

Move g_profiler to profiler.cpp|h

Use a common function to check the reading offset

Also fix a memory leak
Fix overloaded virtual warning in Player::move()
Remove some trailing whitespace

 - General code cleanup
 - Unified object creation and loading
 - Specifying objects in APIs is now orthogonal (i.e. anything can take an ID,
   name string, or the raw table definition (and automatically registers if present

#2583

Because we get a Buffer<u8> from ConnectionEvent, don't convert it to SharedBuffer<u8> and return it to Server/Client::Receive which will convert it to NetworkPacket
Instead, put the Buffer<u8> directly to NetworkPacket and return it to packet processing
This remove a long existing memory copy
Also check the packet size directly into Connection::Receive instead of packet processing

remove command from queue on success, else do nothing, instead of remove command from queue and push it front on success

Move texture_min_size even further down the pipe. Now, textures are JIT-upscaled using an image transformation, right at the time they're added to a mesh or particle; images used in 2D elements are left unscaled. This should fix any remaining issues with HUD elements.

Filename screenshot_ + ISO 8601 format + [-serial]

i.e. screenshot_YYYY-MM-DDTHH::MM::SS[-serial].png

Serial is added if the filename + timestamp already exists and is in the range 1 to 999

Add core.clear_registered_schematics() and refactor schematics somewhat

Invert the meaning of holding down the fast button (i.e. holding down the fast button -- if there is one -- means walk), unless performing an action, sneaking or jumping.
Still requires fast move to be toggled on (and fast priv)