Change to the Application io_service:
* Simplified the implementation and removed class IoServicePool
* The io_service outlives the components of the Application
Remove spurious assert in ResolverAsioImpl
Fix Overlay stop on exit:
The stop sequence for Overlay had a race condition where autoconnect could
be called after close_all, resulting in a hang on exit. This resolves the
problem by putting the close and timer operations on a strand:
* Rename some Overlay members
* Put close on strand and tidy up members
* Use completion handler instead of coroutine for timer
* Use App io_service in PeerFinder
Don't stop accepting on an error in HTTP::Door:
* Errors are always logged when they occur
* An error which is not operation aborted will not stop the accept loop
Fix race conditions closing HTTP I/O objects:
This fixes a case where stop can sometimes skip calling close on some
I/O objects or crash in a rare circumstance where a connection is in the
process of being torn down at the exact time the server is stopped.
[WIP] Add script to start/stop rippled

[WIP] Tweak script
* Use `node bin/stop-test.js 5,10` form instead of ENV_VAR
* Log the rippled  pid
* Don't abort on stalls unless an environment variable set

[WIP] Tweak logging

[WIP] Fix

[WIP] Run through the range again on completion

[WIP] Tweak so can use non integer range elements