Removed query_server_t.
Removed stream_cache_t, and its unused dependents query_language::execute_query and query_language::execute_read_query.
Moved ql_stream_cache.cc to stream_cache.cc.
Removed query_language.cc helper function declarations out of the header file.
Moved more query_language.cc helper declarations (eval_term_as_view, etc) out of the hpp file.
Moved yet more helpers out of query_language.hpp.
Removed WriteQuery3_Update.
Removed WriteQuery3::DELETE.
Removed WriteQuery3_Mutate.
Removed WriteQuery3_Insert.
Removed WriteQuery3_PointUpdate, WriteQuery3_PointDelete, WriteQuery3_PointMutate.
Fixed trivial compilation error with unused variable.
Made WriteQuery3 a nearly vacuous type.
Removed execute_write_query and check_write_query_type functions.
Removed WriteQuery3 and its presence in Query3.
Removed a whole bunch of Builtin types (all the way up to MAP).
Removed Builtin and Term3::Call.