Add support for estimatefee and estimatepriority.
Remove SetId from Cmd interface.
Update test coverage report.
Use default genproclimit of -1 on setgenerate RPC.

The correct default for the genproclimit on the setgenerate RPC is -1.

ok @jcvernaleo.
Change PingTime and PingWait to float64.

This is to match bitcoin-core.  Caught by Skelsey.

Closes #24
IMPORT PATH MODIFICATION CHANGESET
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Please use this changeset as the first one on top of the conformal codebase.
Note that if there are new imports, they need to be changed as part of this
changeset. In general, use "git rebase" on github.com/conformal's version
and apply this changeset first.
Task #396 on Task Board:

Add a GetDepositScript JSON result.

For now it's a stub function