Fixed compile issues on windows

With latest upstream L-Systems treegen.
Bugfixes to item_image formspec method
Add TOCLIENT_SHOW_FORMSPEC to display formspecs at client from lua
Call this 0.4.4-d1 because it has a protocol addition since 0.4.4
Add InvRef:get_location()
Add ServerEnvironment::setNode()/removeNode() to allow setting nodes from the C++ side with proper script-defined initialization/destruction
Replace constant red hurt screen with fade out red
Change the nodenames for dirt -> grass and sapling -> tree abms to match the mapgen aliases
Tilt camera on player damage (tweaked by PilzAdam)
Adjust the maximum alpha of the red hurt screen