M of n entries responses to code review - DON'T REVIEW ALL OF THE CODE

This pull request gives reviewers the opportunity to view my response to their review comments.  Those responses are primarily in two commits:

https://github.com/scottschurr/rippled/commit/af6c602c61fe794e20a5c809cc2839d261f97a3a
https://github.com/scottschurr/rippled/commit/1ec033a3087e91c1528cf71764965d71e7343f5c

My intention in the fairly short term is to take all of the preceding commits plus those two commits and squash the whole mass together so we have a way of identifying the code that has already seen a thorough review.

Additionally, there are two commits that address some of the specific concerns that David raised.  I'll not be squashing those commits soon, but I appreciate any comments you may have on those commits are well.  Those commits are:

https://github.com/scottschurr/rippled/commit/748ec33d901b2f2fc92957bb6dbac873c043dbbb
https://github.com/scottschurr/rippled/commit/80e7d11e2a9df39124112277409bda16c7194b3e