Fix move constructor of aged_unordered_container (RIPD-490)
Fix exception safety in aged containers
Use aged containers in Validators module (RIPD-349)
Tidy up sources
Add validators aged container test
src/README.md:  s/addded/added/
Clean up some docs
* Consistent line endings in rippled-example.cfg
* Rewrite CodingStyle.md. Get down to top priorities
Fix warnings and compile errors
New command line LedgerTool (RIPD-243).

* Retrieve and process summary or full ledgers.
* Search using arbitrary criteria (any Python function).
* Search using arbitrary formats (any Python function).
* Caches ledgers as .gz files to avoid repeated server requests.
* Handles ledger numbers, ranges, and special names like validated or closed.
Allow JsonPath operations.

* Retrieve fields from ledgers using JsonPath expressions.
* Accumulate arbitrary precision numbers retrieved by JsonPath.
* New jsonpath_rw library.
  * Includes decorator, six and ply as dependencies.
Get rid of a few ternaries.