GitLab

- Have a version of bind that allocates a local variable, and
  automatically frees it at the end.
- Only malloced memory can be freed manually.

- Better representation of symbolic integers
- Better representation of symbolic locations
- Support while in the vcg
- Support alloc in the vcg
- A better reification mechanism
- Better proofmode support for mapsto with lists
- Normalize fractions
- Restructure lots of proofs
- ...