-Removed some unnecessary functions in the variadic implementation of HashMap
-Fixed a bug when compiling HashMap with clang that would cause it to always use the non-variadic implementation
-Fixed an issue where mongo replicable could generate an invalid update query if, in a nested array, the parent array shrunk and a (remaining) child array also shrunk at the same time
-Added first mongo replicable unit test to ensure that issue does not regress
-Implemented hash caching in sprawl::String and ReplicableBase::ReplicationKey to improve their performance in hash maps