lemmas to merge a sepL and a sepL2

See merge request iris/iris!735

bi/fixpoint lemmas

See merge request iris/iris!725

Iris 3.5.0 release notes

Closes #435

See merge request !748

Improve documentation of convention for `AsFractional` instances

See merge request iris/iris!747

update package descriptions

Closes #436

See merge request iris/iris!746

Prove missing fractional_big_sepL2

See merge request iris/iris!737

To match the suggestion in
iris/iris!737 (comment 75017).

fixes #437

Editor docs: add information on how to use vim for working with Iris

See merge request iris/iris!744

Normalize focused goal output

See merge request iris/iris!743

Merge the "1 focused goal" line with the subsequent "(shelved: 1)" line,
since this is the new output in Coq 8.15+.

Iris does not currently produce this output, since no test calls `Show`
with shelved goals, but this future-proofs the test normalization.

make f_contractive consistent with f_equiv

See merge request iris/iris!741

relax AsFractional Hint Mode

See merge request iris/iris!740

Optimize iDestruct by avoiding superfluous iRenames

See merge request iris/iris!733

Following up on the previous commit, this slightly generalizes the
lemmas associated to the intuitionistic/spatial/modalelim cases of
iDestruct to support renaming on the fly, and use these to save a
later renaming.

The idea is to avoid unnecessary calls to iRename: when choosing names
for sub-patterns, instead of generating fresh names or reusing an
existing (unrelated) name, if the sub-pattern is an identifier, then
directly chose this identifier as the new name, thus saving a rename
later on.

[triviality] Clarify funny proof of `tac_twp_cmpxchg_fail`

See merge request iris/iris!738