Adding Fist.evaluateAtom() parsing back in

to avoid forcing ViewGraph to make judgments about what different block
names are supposed to be.
Purging selection code

I'm planning to replace that with d3.svg.brush() selections. The
new-style selections will be persistently visible, much like in
http://bl.ocks.org/1667367 - both the complete time-series and the
selected context are visible, allowing for reversible exploration.