First step towards simplifying 'deplish'

Removed all 'example' and 'built-in' nodes since we're changing interface anyway
Removed need for 'executionDataDict' and stuff like that.
Now node can just implement 'execute()' and it will be run upon execution.
Only tested with 'test' node in this case.
Merge remote-tracking branch 'origin/master'

Conflicts:
	deplish/data_packets/sampledatapackets.py
	deplish/data_packets/vcldatapackets.py
	deplish/node.py
	deplish/nodes/marcusnodes.py
	deplish/nodes/samplenodes.py
	deplish/nodes/vclnodes.py
Removed data_packets and all built-in + examples nodes since we're changing execution interface.

Also made sure node just runs upon simple execute() method without extra parameters.
No more 'separate processes' execution.