1.8 becomes 2.0

I'm thinking that 1.7 is a good place to close out version 1. Once it is complete, then on to version 2.

There are several reasons for this. Next on deck is a data conversion, with potential destabalization hazards. And then we start defining Topic types and adding type-specific logic, making the Ark more of an application server than a Wiki. But once we have snapdump capability, version 1 is complete and sustainable.

So 1.8 becomes 2.0. (I've made a few other changes as well.)