- added make-encumbered to effects2input and effects2output.
- added all-efx?-total.
- fixed all theorems so now the output also contains facts from
  context as well as encumbered permission.
removed fracperm, now using 1/2
Merge branch 'write3' into write2
reverted back to e41310e46238d2c0291a0fc7f0340fc3fe43ab1c.
added efx`lt, and efx`leq now use it
- BROKEN version.
- removed commented code.
- defined maybe-efx`no-consume and effects`no-consume
- proved efxmap`join-no-consume-commutative.
Merge branch 'write' into write5
merge
removed efx/none.
removed efx/none.
added efx2frac.
changed comments.
- rewrote. also changed comments.
- added efxmap-minimum-efx/U-inversion with trustme.
- added respects-eq for efxmap-minimum-efx.
- fixed efxmap-minimum-efx, it should start with a MAX efx!
- proved a few theorems about efxmap-minimum-efx.
not-consume-implies-minimum-efx.