Feature - Allow using Multiple schemaTypes

[Ibigpapa]

Running the following will only select the SCHEMA and not TABLE COLUMN

./pgdiff -U <user> -W <pass> -H <host> -D <db> -O <options> -S <schema> \
-u <user> -w <pass> -h <host> -d <db> -o <options> -s <schema> \
SCHEMA TABLE COLUMN

-- schemaType: SCHEMA
-- db1: {<db> <host> <port> <user> <password> <schema> <options>}
-- db2: {<db> <host> <port> <user> <password> <schema> <options>}
-- Run the following SQL against db2:

Ideally this would actually run all 3 SCHEMA TABLE COLUMN in specified order or combined.