* limit the number of StatementTmpl in CustomPredicate:
- add constructor method for CustomPredicate
- make size checks at the CustomPredicate creation, so that once instantiated we can assume that contains valid data
This resolves#79
* Update tests to use new interface
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Co-authored-by: Ahmad <root@ahmadafuni.com>
* Experiment with statement & op enums
* Clean-up & fixes
* More clean-up
* Add argument length checks
* More clean-up
* Place statement and operation logic in submodules