Update cabal dependencies.
Fix up type errors; graph-algorithms builds now.

TODO: figure out why `HasPut`, `HasGet`, etc. aren't working -- as far
as I can tell explicitly writing out `'Ef 'P 'G b f i` shouldn't be
necessary.

It also might be better to give `NatArray` its instance of `DeepFrz`
within its own file.
Ignore cabal sandboxes.
Change 0	~/Documents/parfunc/lvars/haskell/lvish-graph-algorithms
1	~ to  for effect levels sigs.
Merge pull request #87 from iu-parfunc/update-graph-algorithms

Update graph algorithms