Do not hard fail if imports fail for one project.

It may be the case that we have already re-imported
some of the data, so we just move on to the next
project.

bin/system_imports.py

@@ -9,7 +9,7 @@ import os
 from glob import glob
 import configuration
 import preplots
-from datastore import Datastore
+from datastore import Datastore, psycopg2
 
 exportables = [
 	"events_seq",
@@ -38,11 +38,14 @@ if __name__ == '__main__':
 				print("Survey does not define an export path for machine data")
 				continue
 
+			try:
 				for table in exportables:
 					path = os.path.join(pathPrefix, table)
 					print(" ← ", path, " → ", table)
 					with open(path, "rb") as fd:
 						cursor.copy_from(fd, table);
+			except psycopg2.errors.UniqueViolation:
+				print("It looks like data for this survey may have already been imported (unique constraint violation)")
 
 			# If we don't commit the data does not actually get copied
 			db.conn.commit()