Split out the local backend (#2052)

This splits the backend into two parts: the local backend for desktop cellxgene and the AWS backend for hosted cellxgene. The local backend is in local_server while the hosted remains in server. The general idea is to copy everything from server to local_server, pull unneeded stuff out of local_server, and keep server as-is for this PR. Not touching server means all the infra and deployment code will continue working just as it did before so we can make those changes incrementally.

local_server/data_common/fbs/NetEncoding/JSONEncodedArray.py

@@ -0,0 +1,46 @@
+# automatically generated by the FlatBuffers compiler, do not modify
+
+# namespace: NetEncoding
+
+import flatbuffers
+
+class JSONEncodedArray(object):
+    __slots__ = ['_tab']
+
+    @classmethod
+    def GetRootAsJSONEncodedArray(cls, buf, offset):
+        n = flatbuffers.encode.Get(flatbuffers.packer.uoffset, buf, offset)
+        x = JSONEncodedArray()
+        x.Init(buf, n + offset)
+        return x
+
+    # JSONEncodedArray
+    def Init(self, buf, pos):
+        self._tab = flatbuffers.table.Table(buf, pos)
+
+    # JSONEncodedArray
+    def Data(self, j):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
+        if o != 0:
+            a = self._tab.Vector(o)
+            return self._tab.Get(flatbuffers.number_types.Uint8Flags, a + flatbuffers.number_types.UOffsetTFlags.py_type(j * 1))
+        return 0
+
+    # JSONEncodedArray
+    def DataAsNumpy(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
+        if o != 0:
+            return self._tab.GetVectorAsNumpy(flatbuffers.number_types.Uint8Flags, o)
+        return 0
+
+    # JSONEncodedArray
+    def DataLength(self):
+        o = flatbuffers.number_types.UOffsetTFlags.py_type(self._tab.Offset(4))
+        if o != 0:
+            return self._tab.VectorLen(o)
+        return 0
+
+def JSONEncodedArrayStart(builder): builder.StartObject(1)
+def JSONEncodedArrayAddData(builder, data): builder.PrependUOffsetTRelativeSlot(0, flatbuffers.number_types.UOffsetTFlags.py_type(data), 0)
+def JSONEncodedArrayStartDataVector(builder, numElems): return builder.StartVector(1, numElems, 1)
+def JSONEncodedArrayEnd(builder): return builder.EndObject()