SERVER-15486 jstest fix
SERVER-15486 parse_log_component_settings
SERVER-15486 LogComponentVerbositySetting validation

Implement _set via parseLogComponentSettings.

Also extract most of LogComponentVerbositySetting.append to new method _get.
Remove need to prune mutablebson doc produced by _get.
Replace typedefs with 'using'.
SERVER-13635 take ownership of shard key in shardCollection
Merge remote-tracking branch 'upstream/master'