Draft for a Listener Interface on IRScopes:

1. add of instr to the scope
2. begin and end (with its Operand result) of IRBuilder.build()

1. enables traceability from scope to its instructions and 2. the mapping of an
IRScope to its (AST)Node
Wrapper for notfications on a List<Instr> (used in BasicBlock)
Listener on changes of a List<Instr> for instance inside of a basic block:

1. models the operation of modification
2. callback function to specify what going to change
boilerplate + trivial ws changes
Stub for own listIterator with eventing
Merge
Custom ListIterator without eventing, yet
Save co I can cp next commit
Add of listener to list iterator and as private field inside of the list wrapper
Add and remove on list with listener; Implementation for listIterator(index)
Completed implementing the list with orthogonal calls into primitive calls (listIterator, retainAll) with eventing as side effect
addAll(Collection) emits events
Merge
Injecting of InstructionListener to IRManager
Commit so I can cp
getInstructionsListener() to request the listener
Wrap the instructions of basic blocks, plugin the listener
Fixed imports
Fixed imports
equals(Object) based on scopeId