[BioPython] Deprecating Bio.PubMed and some of Bio.GenBank

[Peter]

Dear Biopythoneers,

Those of you who looked at the release notes for Biopython 1.48 might
have read this bit:

>> Bio.PubMed and the online code in Bio.GenBank are now considered
>> obsolete, and we intend to deprecate them after the next release.
>> For accessing PubMed and GenBank, please use Bio.Entrez instead.

These bits of code are effectively simple wrappers for Bio.Entrez.
While they may be simple to use, they cannot take advantage of the
NCBI's Entrez utils history functionality.  This means they discourage
users from following the NCBI's preferred usage patterns.

We're already trying to encouraging the use of Bio.Entrez by
documenting it prominently in the tutorial (which seems to be working
given the recent questions on the mailing list), but for Biopython
1.49 I'm suggesting we go further and deprecate Bio.PubMed and the
online code in Bio.GenBank.  This would mean a warning message would
appear when this code is used, and (barring feedback) after a couple
of releases this code would be removed completely.

Any comments or objections?  In particular, is anyone using this
"obsolete" functionality now?

Peter