add EDF optimality argument

This patch adds the classic EDF optimality argument: by swapping
allocations, any schedule in which no job misses a deadline can be
transformed into an EDF schedule in which also no job misses a deadline.
6 jobs for master in 6 minutes and 7 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Build
passed #39802
1.8.0-coq-8.8

00:02:01

passed #39804
1.9.0-coq-8.9

00:02:04

failed #39803
allowed to fail
1.9.0-coq-dev

00:00:15

 
  Process
passed #39806
doc

00:02:59

passed #39807
proof-length

00:00:17

passed #39805
validate

00:04:02

 
Name Stage Failure
failed
1.9.0-coq-dev Build There is an unknown failure, please try again
COQC util/powerset.v
COQC util/seqset.v
File "./util/seqset.v", line 19, characters 42-52:
Error: The reference mkPredType was not found in the current environment.

make[1]: *** [Makefile:659: util/seqset.vo] Error 1
make[1]: *** Waiting for unfinished jobs....
make: *** [Makefile:321: all] Error 2
ERROR: Job failed: exit code 1