Additional Flow Meter Support

I would like to see the following newer flow meters supported.

CST ELF Series Flow Sensors - https://www.creativesensortechnology.com/copy-of-pct-120

Models:
ELF-T10-N01
ELF-T75-P01

Both models appear to be calibrated at K=0.153 Offset=1.15

They have 4x lower flow rate sensitivity (0.2 gpm) than the FSI series currently supported and use the same signal protocol.