Contextual summaries, pgtextindex on branch1

[Paul Everitt]

After we get migration, rsync, Youth Initiative, etc. behind us, let's get our plan together for evaluating pgtextindex.

I propose that we use branch1 for this. branch1 is the special branch, the one with long-term assumptions. Thus, it will be the branch where we condition OSF to spend more time. It makes a good target for using pgtextindex in anger.

Let's get branch1 running without RelStorarge, with pgtextindex, and with contextual summaries. The latter probably means merging to the trunk.

We need to make sure of course that pgtextindex doesn't accidentally go into production on the May 5 update.