Using typefefs for key and value types. Removing notifier et al.
create a GetItertor function on storage_manager.  change storage_manager to take a db module reference instead of pointer.
Convert value_key to be a string, formerly a vector<uint8_t>
Modifies Makefiles to build the .cc src file.  Changes to throw versus exit and log.  Changes iterators to use 3 values, essentially streamId, start key and endKey. Puts more magicin Done() and Next() functions
do not show build directories
Change leveldb interface to throw instead of returning a status type. some optimizations and cleanup. Complete removal of DbmStatus object