- Add a generalized client store made up of a key, profile, and trusted certs store. Each sub store can support different backends (~/.tsh, identity_file, in-memory).
- Replace custom identity file handling with in-memory client store.
- Fix issues with trusted certs handling.
We were inconsistent throughout the codebase and would sometimes
use the slices package and other times use our own equivalents
in api/.
This removes our versions in favor of the golang.org/x package that
does the same, which has the added benefit of reducing the surface
area of the public API module.
Note: despite existing uses of the slices package, for some reason
it didn't show up in go.mod or go.sum. Fixed that too.
Brian Joerger