Many things. See more

- Fixed nbody removing taskloop.
- moved to last nosv branches
- use small problem sizes and increase the number of iteratios for easy
  tweaking to match same execution time

NBODY (unfinished) /nix/store/8qwkvkdwzfpwaypb2j7bf1jhzby90lcp-plot
HEAT: /nix/store/13zdkb22qd81sw98ycp7nxmr2gz307fi-plot
HPCG: /nix/store/chms703q8l4pkrm375j9fglc1qkyjjck-plot