More consistent naming for `auth`.

See merge request iris/iris!250

This MR is a follow up on the renamings performed (implicitly) as part of
!215. This MR makes the following changes:

- `auth_both_frac_valid` and `auth_both_valid` are now of the same shape
  as `auth_both_frac_validN` and `auth_both_validN`. That is, both are
  now biimplications.
- The left-to-right  direction of `auth_both_frac_valid` and
  `auth_both_valid` only holds in case the camera is discrete. The
  right-to-left versions for non-discrete cameras are prefixed `_2`, the
  convention that we use throughout the development.
- Change the direction of lemmas like `auth_frag_valid` and
  `auth_auth_valid` so that it's consistent with the other lemmas. I.e.
  make sure that the ◯ and ● are always on the LHS of the biimplication.

Make authoritative part of auth fractional

See merge request iris/iris!215

Make `iFresh` faster

See merge request iris/iris!247

Export that iPreProp is a Cofe

See merge request iris/iris!246

Generalize `iPureIntro` to support non-empty spatial contexts with just affine hypotheses.

See merge request iris/iris!241

Never used `Declare Instance`.

Add an `iSimpl in "%"` test.

See merge request iris/iris!240

Disable new warnings for Coq master

See merge request iris/iris!242

A more intuitive proof that lists from a COFE

See merge request iris/iris!239

Add synopsis so make build-dep does not complain

See merge request iris/iris!238

Paolo G. Giarrusso authored 5 years ago and Ralf Jung committed 5 years ago

Nitpick, yes, but I've seen the complaint enough times today to bother.

That complaint is only useful to maintainers, and it's even in color.

```
[WARNING] Failed checks on coq-iris-builddep package definition from source at file:///Users/pgiarrusso/git/Coq/0IRIS-SWITCH/iris/build-dep:
    error 57: Synopsis and description must not be both empty
```

This proof also more easily scales to other recursive types, like
trees etc.