WIP Cleanup backend to prepare for review

Author: IvoDD

.gitmodules

@@ -19,6 +19,3 @@
 [submodule "cpp/third_party/entt"]
 	path = cpp/third_party/entt
 	url = https://github.com/skypjack/entt.git
-[submodule "cpp/third_party/date"]
-	path = cpp/third_party/date
-	url = https://github.com/HowardHinnant/date.git

cpp/arcticdb/version/python_bindings.cpp

@@ -812,6 +812,9 @@ void register_bindings(py::module &version, py::exception<arcticdb::ArcticExcept
         .def("batch_append",
              &PythonVersionStore::batch_append,
              py::call_guard<SingleThreadMutexHolder>(), "Batch append to a list of symbols")
+        .def("batch_update",
+            &PythonVersionStore::batch_update,
+            py::call_guard<SingleThreadMutexHolder>(), "Batch update a list of symbols")
         .def("batch_restore_version",
              [&](PythonVersionStore& v, const std::vector<StreamId>& ids, const std::vector<VersionQuery>& version_queries, const ReadOptions& read_options){
                  auto results = v.batch_restore_version(ids, version_queries);