Merge pull request #7 from jasperges/master

Expanded the math node (made is consistent with the Cycles math node)
implement "all" as allowed input type
subprogram socket
SubProgramNode
small fix
sub program start node
generate correct input list
minor change
function gets called now
works a bit
had first small loop runnning
cleanup
cleanup
compile testing
minor change
solve exec issue with more a subprogram in a subprogram
cleanup
add sockets to loop
better socket management
cleanup