[9.1] 2 bugs with extensions

I converted Skytools modules to extensions and found 2 problems:

1) Dumpable sequences are not supported - if sequence is tagged  with pg_catalog.pg_extension_config_dump(), the
pg_dumptries  to run COPY on it.
 

2) If there is schema with functions, but nothing else,  then when later converting it to extension by adding
functionsand schema to extension, later drop  of that extension fails to remove schema.  Proper CREATE EXT + DROP EXT
worksfine.
 

To reproduce, checkout 'master' branch and go directly
to module directory:

$ git clone --recursive git://github.com/markokr/skytools.git
$ cd skytools

1) $ cd sql/pgq && make install installcheck
..
pg_dump regression > test.dump
pg_dump: SQL command failed
pg_dump: Error message from server: ERROR:  cannot copy from sequence
"batch_id_seq"
pg_dump: The command was: COPY pgq.batch_id_seq  TO stdout;


2) $ cd sql/pgq_coop && make install installcheck
..create extension pgq_coop from 'unpackaged';drop extension pgq_coop;create extension pgq_coop;ERROR:  schema
"pgq_coop"already exists
 

-- 
marko