#59 Renaming the schema leaves the sequences behind in GTM

[knienart]

It seems that when a schema is renamed (via alter schema xx rename to yy) sequences in the GTM are not renamed and left in the gtm.control with the old names.

It causes awkward errors if one wants to create a new sequence in a new schema with a xx name:

ERROR: GTM error, could not create sequence (from gtm_seq.c:185).

This misbehaviour shows up in the trunk.