Resolve "Removing Operation from SFG"

• Adds function to sfg that can remove an operation specified by id as long as it has the same amount of inputs and outputs.
• Adds tests that verifies this function.

Closes #85 (closed)

b_asic/operation.py

@@ -193,6 +193,7 @@ class Operation(GraphComponent, SignalSourceProvider):
         """
         raise NotImplementedError
 
+
 class AbstractOperation(Operation, AbstractGraphComponent):
     """Generic abstract operation class which most implementations will derive from.
     TODO: More info.