compiler, runtime, common: Support (in)out Parameters

When a function is called, if there is an (in)out parameter,
make sure that updated values are propogated to the calling
function.

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>

Sources/P4Runtime/Protocols.swift

@@ -28,7 +28,8 @@ public protocol EvaluatableParserState: P4DataValue {
   func state() -> ParserState
 }
 
-public protocol CallableExecution<T> {
+/// Defines an interface for P4 components that can be invoked directly by the p4rse library user
+public protocol LibraryCallable<T> {
   associatedtype T
   func call(execution: ProgramExecution, arguments: ArgumentList) -> (T, ProgramExecution)
 }