Add ExtendedCall to PLCObject as a replacement of RemoteExec and reflect it in eRPC interface.

ExtendedCall is a generic remote procedure call that runtime code can register to and that IDE extensions can call.
For example a fieldbus extension can use ExtendedCall to browse the fieldbus devices connected to the runtime.

input,in_topiccc,1,outer,0
input,in_topic1,1,DINT,1
output,out_topiccc,1,False,datatype0,0
output,out_topic1,1,False,DINT,1