Modify adequacy proof to not break the 'fancy update' abstraction. Modify fupd plainly interface and add new derived results.

Prophecy variables

See merge request FP/iris-coq!173

Support multiple steps in `PureExec`.

See merge request FP/iris-coq!179

Snapshot will re-appear in iris-examples eventually

Marianna Rapoport authored 6 years ago and Ralf Jung committed 6 years ago

- Removing admitted prophecy spec and making prophecy-related examples (coin-flip and atomic-pair-snapshot) work with the new prophecy support in heap_lang
- Adjusting heap_lang tactics for automation of substitution, closedness, etc. to support prophecy syntax
- Adding notation for prophecy syntax