PeerFinder adjustments:
* If no [ips] are specified, use r.ripple.com
* Use different backing stores for PeerFinder and Validator databases
Check for gcc 4.8 and fix boost linking on Debian
[FOLD] Remove obsolete function and move to std functions
[FOLD] Cleanup VotableInteger class, remove unused duplicate
[FOLD] Make isMemoOkay a free function
[FOLD] Fix typos
[FOLD] Sanitize error returns
[FOLD] Refactor: move transactors out of the way