Implement basic sentiment analysis using good/badword lists.

Fixes #24 well enough. Don't think actually using the real deal
is needed right now.
Fixed off by ones in Lorem Ipsum generator.

Fix sent upstream as 016a5c695d901cb32e109ca0460e9bf385d15f04 at
https://github.com/oliverdodd/sclorem/pull/1 .
Make accumulator a pure sink.
Make FlowFrequency operational and add some eyecandy.

Don't bother saving the FlowObject. We can't really use it anyways.
If we limit ourselves to the string representation things are
pretty straight-forward. Also fixed broken sort. I should get rid
of the notion of anything being in-place in scala ;) Note that
while the list growing/shrinking is exposed growing is broken
once the list has entries > 1

Display in GUI is in form of a table listing position, word and value.

Also fixed groupings and choose nicer icons in node selector.