Source formatting.

Don't set up own statement handles but use Datastore::run_query instead.
Fix product output in tab-delimited text and Excel files when line
feed/new line characters included.

Source formatting and use of Datastore::run_query. 

This causes problems with the length calculation used to decide whether
to truncate the label. 

Use existing scheme view. 

This is calculated by records x loci.  This can be overridden by setting
the seq_export_limit attribute in the system tag of config.xml.

There may be times when it will be desirable to merge isolate databases,
perhaps to incorporate a local private database with a copy of a public
database. This will be easier if the id numbers in the two databases are
different.  Set the start_id attribute in system tag to define.

Submitters can edit any isolate submitted by themseleves or any member
of a user group that they belong to.