Minor formatting.

give warning if strain is not in database or for this particular strainSlice, there is no genotype data available in new method

to be in line with other Ensembl code.

Synopsis and STEDRR msg updated to alert users to include the -update option
when writing analysis_descriptions to the DB.

added a multispecies_db example to clear up confusion between is_multispecies method an multispecies_db parameter

warning added if you don't use the -write option

port changed to 3306