Refactor db replicator - split into initial / realtime (#136)

Author: bakwc

mysql_ch_replicator/common.py

@@ -0,0 +1,7 @@
+from enum import Enum
+
+class Status(Enum):
+    NONE = 0
+    CREATING_INITIAL_STRUCTURES = 1
+    PERFORMING_INITIAL_REPLICATION = 2
+    RUNNING_REALTIME_REPLICATION = 3