* impl AugmentedFCircuit non-base case

* add multiple iterations to AugmentedFCircuit test

* implement base case on AugmentedFCircuit and test

* Update cmE of E=0-vec to work as zero point

Update cmE of E=0-vec to work as zero point instead of as cm(0-vec)

* patch r1cs-std dep to a cherry-picked version with the zero-scalar-mult fix

* refactor FCircuit to make it more suitable inside the AugmentedFCircuit