Change argument parsing to take defaults as an argument.

In preparation for supporting arguments supplied via pragma.
Added support for setting options by pragma.
Distinguish between && and & operators.

Because && short circuits, while & does not.
Distinguish between logical and bitwise or operator.
Add support for recursive generators.
Re-organized nqueens directory to be prettier.
Cleaned up performance gathering for nqueens.
Updated R script to produce nice comprehensive graph of nqueens perf.
Re-organized sudoku directory to clean it up a bit.
Added support for reorder block.

It scales so poorly, it doesn't work for more than 2 statements, but
I think that's not due to the reorder implementation, but other scaling
issues. I hope.
Switch to newly supported auto-deriving of Eq in shampi.
Remove RebindableSyntax pragmas.

Because smten no longer uses them, and they shouldn't have been put explicitly
anyway.
Updated for smten with support for auto-deriving of Show.