[Evolution-hackers] Can I remove some old migration cruft, pretty please?

[Matthew Barnes <mbarnes redhat com>]

Would anyone object to me removing the migration code from the old mail
summary files to SQLite?  Believe it or not it's been three years since
we started using SQLite back in Evolution 2.24.

Removing that stuff would help lighten my workload on the account-mgmt
branch, and there's still a good deal of cruft in Camel related to the
old summary files that could be purged.

Users upgrading from versions 2.22 or older will just have to regenerate
their mail caches from scratch.  I don't think that's unreasonable.

Gotta finish up my own migration gunk first, then I'll tackle this later
in the week unless it proves too controversial.

Matt