Correct wrong format strings

[rafatower]

contrib_regression=# select format('CREATE SEQUENCE %s START WITH %d', 'hola', 3+2);
ERROR:  unrecognized conversion type specifier "d"
contrib_regression=# select format('CREATE SEQUENCE %s START WITH %i', 'hola', 3+2);
ERROR:  unrecognized conversion type specifier "i"
contrib_regression=# select format('CREATE SEQUENCE %s START WITH %s', 'hola', 3+2);

This affects current code: https://github.com/CartoDB/cartodb-postgresql/blob/master/scripts-available/CDB_CartodbfyTable.sql#L168

[rafatower]

http://www.postgresql.org/docs/9.4/static/functions-string.html#FUNCTIONS-STRING-FORMAT

[rafatower]

Also this ticket needs a test case to force the execution path through the faulty code.