[math] VECTx_NORM updates

- norm functions/macros return the scalar value, don't take norm as arg
- remove some type specific macros where the generic ones can be used
[math] add double versions for vect3/quat norm
[math] rmat|quat_identity functions
[math][ins] rewrite/move some math to ins_float_invariant

- use float_quat_vmult instead of FLOAT_QUAT_RMAT_B2N|N2B
- use float_quat_derivative instead of float_quat_vmul_left