When we get all slices that has genes on them, and we find a slice that
is not a reference slice, make sure that we only fetch the unique region
of it.  This solves the problem of genes getting new stable IDs even
though they haven't changed.

Check the result of the print and die if we have an error. Bits of flatfiles have been missing so hopefully these will now be caught

Moved the warning about the cache not being on back into the constructor & simplified the construction method for the cache. If someone doesn't inherit from this correctly they'll loose the warning but that is all.

Ensembl core is now at v65. Patches to work with flat file handles in core like databases and supporting checksum derived xrefs

Replaced RefSeq_dna_predicted with Refseq_mRNA_predicted and RefSeq_ncRNA_predicted as the RefSeq_dna_predicted have been split for release 64.

Merging of UniParc mapping code into the Xref system. This relies on being able to contact the EBI based UniParc readonly database.