GitLab

1) Formalize the notion of weakly sustainable policy, along with
its contrapositive, and prove the equivalence between the two.

2) Establish weak sustainability of self-suspending tasks w.r.t.
execution times and variable suspension times, based on the
transformation we had formalized.

- Added definitions and implementation of jitter-aware RTA for
  uniprocessor scheduling.
- The Prosa directory was restructured to better accomodate the different
  types of arrival sequences and schedules.

- Add generic definition of job suspension based on the cumulative service
- Define the dynamic suspension model (based on task suspension bounds)
- Add suspension semantics for uniprocessor schedules
- Formalize reduction from suspension-aware schedule to suspension-oblivious
  schedule by inflating costs (works with JLDP policies and non-unique priorities)
- Formalize suspension-oblivious FP RTA using the reduction
- Add implementation of a concrete suspension-aware scheduler
- Test suspension-oblivious FP RTA with an actual task set
- Add simpler definition for JLFP policies
- Generalize busy interval lemmas from FP to JLFP scheduling