Write general replacer code

Append var to called predicate args, parent header
Keep labels of args to give to child pred header 
- with alg code num
v1_1 first instance of variable from first group

_1, _2 adjacent in parent header

X

write code myself, just chunk code and access later in aw db
- if nec, use similar idea to above with variable group types such as "Acts on var n"