Typed prophecy variables + cleanup
This MR introduces the following changes:
- new folders
- things unrelated to logical atomicity moved from
theories/logatomto the new folders,
- a more complete typed prophecy interface (supporting one-shot prophecies) that is now usable,
- examples using the typed prophecy interface (lazy coin + clairvoyant coin),
- specs for all the coin examples, eager implementation for the eager spec.
@jung: the coin examples of the Iris repository are included in a modified version, mainly linking them to their spec.