0.7-0.8 compatibility (incl. testing)

It appears reasonable for us to restore, then maintain compatibility 
between Pygr 0.7 and 0.8. The following tasks have been recognised as 
necessary to restore such compatibility:
 - add compatibility code to 0.8 which would allow it to read 0.7 
annotation pickles;
 - release a new Pygr-0.7 version which would allow it to read 0.8 
pickles, as well as to talk to 0.8 XML-RPC servers. Note that at this 
point it isn't clear annotation pickles are the only ones to have changed 
so we should perform appropriate tests (see below) before such a release 
is issued.

Moreover, in order to make sure no incompatibilities other than XML-RPC 
and annotation pickles exist, we should set up cross-version tests. This 
would involve the following:
 - deciding whether this code should be standalone or a part of our 
testing framework;
 - preparing appropriate pickles (sequences, annotations, aligmnents) for 
both versions;
 - setting up a 0.7 XML-RPC server and telling the testing code, via 
appropriate configuration keywords, which such a server (or servers) can 
be found.

Original issue reported on code.google.com by mare...@gmail.com on 21 May 2009 at 12:09

graehl / pygr

0.7-0.8 compatibility (incl. testing) #91