add data fsktonrz fsk cleaning util (#352)

add fsk cleaning / demod tool fsktonrz
- used old fskdemod for HID and adjusted it to build the tone tables for any fsk model detected or given.  using the tone tables we are able to convert the fsk to clear strong NRZ/ASK even with very weak fsk waves.
- also fixed a small textual bug in `lf search u` output
- also added more graph clearing code to help ensure the demod overlay doesn't show when it shouldn't...
- and improved strong NRZ clock detection.
- fixed bugs in places it used old static values instead of dynamic read values. and removed redundant items.