liquid_kind was declared as an u8, but used to hold a content_t value, which is delcared to be a u16.

changing this fixes (at least for me) the problem reported in bug #414.

Previously, when a block was activated, on_timer callbacks where
called with the relative position of the node inside the block,
instead of the absolute position of the node.

Since commit 5a13c494 when I'm in a new area of the world that hasn't
yet been generated the debug log gets flooded with the following error:

Map::setNode(): Not allowing to place CONTENT_IGNORE while trying to
replace "default:dirt_with_grass" at (729,1,-219) (block (45,0,-14))

This commit fixes that.

Can be turned off in the key change GUI or in minetest.conf via doubletab_space

Configure using repeat_rightclick_time in minetest.conf

Add ServerEnvironment::setNode()/removeNode() to allow setting nodes from the C++ side with proper script-defined initialization/destruction

With latest upstream L-Systems treegen.

Fixed the compiler not being able to determine which symbol it should
use when compiling Minetest as 64bit with Irrlicht 1.8+