Refactor string-to-integer conversions
Cleanups:
* Remove obsolete config variables
* Reduce coupling
* Use C++11 ownership containers
* Use auto when it makes sense
* Detect edge-case in unit tests
* Reduce the number of LedgerEntrySet public members
Add ledger cleaner documentation (RIPD-555)
Add is_short_read()
Fix handling of HTTP/S keep-alives (RIPD-556):
* Proper shutdown for ssl and non-ssl connections
* Report session id in history
* Report histogram of requests per session
* Change print name to 'http'
* Split logging into "HTTP" and "HTTP-RPC" partitions
* More logging and refinement of logging severities
* Log the request count when a session is destroyed