How to pass travel times and takeoff angles?

[rmodrak]

Currently, there are a number of ways of specifying travel times and takeoff angles, not just taup_model calculations, but also FK_metadata and so on.

There may some opportunities for improved ease of use-- for example, through greater consistency between data processing, waveform misfit and polarity misfit and so on.

Over time we might consider deprecating FK_metadata, CPS_metadata or other options tied to legacy solvers/ nonstandard metadata in favor of a very general user supplied dictionary?