This is not yet the final organization, but already an improvement.

Move main high-level results to separate top-level `results` module.
Rationale: Let's make it very clear where to find the main, high-level
results in Prosa, and at the same time let's declutter the analysis
namespace.

Other notable change, apart from moving files around:

- move two key analysis definitions to analysis.definitions
- split RBF definition and facts into separate files
- move facts about ideal schedule to ideal_schedule.v

This fixes all warnings about ambiguous module names and resolves #49.

It also highlights that we still need to cut down on superfluous
Require Import commands in recently ported files.

This avoids the need to use @-notation when establishing platform
properties (e.g., in facts about ideal schedules).

Thanks to Maxime for the suggestion.

Rationale: reserve the behavior folder for trace-based semantics.

These lemmas really constitute an analysis of the basic consequences
arising from the chosen semantics and hence logically belong to the
"analysis" part of Prosa.

This patch adds functions for transforming a given schedule either by
replacing the allocation at a given point, or by swapping the allocations
at two points, together with a bunch of supporting lemmas and service
invariants.