bits: Add from_f32le, to_f32le, ...

[wader]

TODO:

• should somehow generalize to/from encodings?
• move code to somewhere else?

[wader]

Needed this for some work stuff, should probably to done in a nice way, usage:

$ go run . -n '"C76E9EBE" | from_hex | from_f32le | ., to_f32le'
-0.30943891406059265
   │00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17│0123456789abcdef01234567│
0x0│c7 6e 9e be│                                                           │.n..│                   │.: raw bits 0x0-0x3.7 (4)