Estimate susceptibility

[MKrbm]

The last objective is estimate any local physical quantities.

[MKrbm]

encountered problems :

1. Perhaps involve with long range sigma z correlation at different imaginary time.

[MKrbm]

Estimate

1. susceptibility (second derivative with magnetic field)
2. square of magnetization
3. specific heat

[MKrbm]

Next need to implement head-tail detached measurement for square of magnetization and susceptibility.

[MKrbm]

Also I will prepare google test from now on.

[MKrbm]

Since the update the estimation work incorrectly. Need to fix