[Ushiba, Komori]

We implemented the PRM length damping filter as well as PR2 (klog:30633) and PR3 (klog:30659).

The attached figure shows some transfer functions.
The closed-loop transfer function represents reduction at the resonant frequency without large gain peaking nearby.

Now we finished imlementing the damping filter from the L oplev to the BF in all of three Type-Bp suspensions.