The active probability estimator can be switched dynamically using the
`Set/GetMissionControl` API, maintaining backward compatibility. The
lncli commands `setmccfg` and `getmccfg` are updated around this
functionality. Note that deprecated configuration parameters were
removed from the commands.
We deprecate `QueryProbability`, as it displays the same information as
`QueryMissionControl` less the probability. `QueryRoutes` still contains
the total probability of a route.
This commit was previously split into the following parts to ease
review:
- 2d746f68: replace imports
- 4008f0fd: use ecdsa.Signature
- 849e33d1: remove btcec.S256()
- b8f6ebbd: use v2 library correctly
- fa80bca9: bump go modules
Having one file per sub command seems a bit too excessive and isn't
really implemented for any of the other commands. So we just group the
Mission Control commands into their own file for now.
