Refactor gwpy.astro.inspiral_range to sensemon_range
Created by: alurban
This PR refactors two functions under gwpy.astro
to more appropriate namespaces:
inspiral_range --> sensemon_range
inspiral_range_psd --> sensemon_range_psd
This also includes a number of minor enhancements for efficiency.
The old functions are now placeholders which (via decoration) raise a DeprecationWarning
so they can be replaced by more refined models that incorporate cosmological corrections in gwpy-2.2.0. This is related to #1292 (closed) and should be merged well before #1284.