add /loadalign load with player orientation and various helper functions

** worldedit_commands/init.lua **
add /loadalign which replaces /load (with player orientation, optional offset, better error checking, and unknown mod list), 
/loadaligntest which replaces /allocate (same improvements)
/loadalignpos and /loadalignpostest do same but use pos1 for location (but orientation from player)
optional /load and /allocate replacement commands are commented out currently
/correctorigin - move pos1 to the origin of the region
/loadalignoffset - set/clear the offset for above commands

** worldedit/serialization.lua **
deserializeAlign can replace both .deserialize and .allocate
optional .deserialize and .allocate replacement functions are commented out currently
.screwdriver_handler - helper fn to rotate nodes after being added by .deserializeAlign (hopefully not required)
.getNewRotation - helper fn to correctly set node rotation before being added by .deserializeAlign
.knownMod - check if mod is enabled for current world
.minmax - move pos1 to origin