add ldv_migrate script

ldv_migrate/bin_xxx/ldv_migrate

-#!/usr/bin/env python3
-
-import ldv_migrate
-migrate_ldvadmin_to_ldvspec.main()
\ No newline at end of file

ldv_migrate/ldv_migrate/connection/retrieve_db_connection.py

 import sys
 
 import psycopg2
-try:
-    from connection.config import read_config
-except:
-    from ldv_migrate.connection.config import read_config
-
 import logging
 import argparse
 from sshtunnel import SSHTunnelForwarder
 import os
 
+from ldv_migrate.connection.config import read_config
 
 def connect_postgresql(section):
     """ Connect to the PostgreSQL database server """

ldv_migrate/ldv_migrate/migrate_ldvadmin_to_ldvspec.py

@@ -22,18 +22,10 @@ import argparse
 import sys
 import math
 
-try:
-    # local imports
-    import connection.retrieve_db_connection as connector
-    from ldv_specification_interface import LDVSpecInterface
 
-except:
-    # installation imports
 import ldv_migrate.connection.retrieve_db_connection as connector
 from ldv_migrate.ldv_specification_interface import LDVSpecInterface
 
-
-
 logger = logging.getLogger(__file__)
 handler = logging.StreamHandler(sys.stdout)
 handler.setLevel(logging.INFO)