Make hitting players make a visual damage flash to the player texture and the screen of the local player

Remove stuff made obsolete by making players more ActiveObject-like and raise protocol version number by one (because it is not compatible at all anymore)

Remove +"^[forcesingle" from ContentFeatures::setInventoryTexture, because 1) it was not used, 2) if it will be used, it won't need to do that anymore

Fix getTextureRaw to always return an image that is not in the texture atlas and fix plain "^[forcesingle" handling

Fix processing of the default_password setting. It is now actually used as the plaintext password for new users. Also add /setpassword and /clearpassword server commands that can be used by admins with the PRIV_PASSWORD privilege, and update the /help message.

Make camera.cpp Irrlicht 1.8-compatible by calling ITexture::lock differently depending on the irrlicht version.

Wireshark dissector: Add TOSERVER_RESPAWN and TOCLIENT_DEATHSCREEN, plus some failed assertion fix (well, hack).

A spurious semicolon after the conditional checking for the drop count
to be not higher than the owned count caused the subsequent
    count = getCount()
to be always executed. Fix by removing the extra semicolon.

Some compilers complain when a class is declared as a struct or vice
versa. Fix by making sure that the correct tag is used both in
declaration and definition.

Fix deadlock if MeshUpdateThread asks new textures while it is being stopped (happened if texture data was transferred slowly)

Move NodeMetadata prototype containers to content_nodemeta.cpp to fix them not being filled correctly on some systems and compilers