Changed wavelength computation to native method within RTKLIb. The native method
should also help in the PVT computation of GLONASS satellites as it considers
the freq. offset when computing the wavelength. This also fixes typo in tracking
stage for MEO satellites of the BDS constellation.
Note: A similar approach to carrier wavelength computation should be applied to
the obs_data in rtk_solver. In theory, static allocation should not be needed for
the types.
This works builds up upon J. Arribas work for unified symbol dec in tracking.
Fixes a couple of bugs with PVT code and adds new code for RINEX functions. Adds
cosmetic fixes to the code with unused variables.
