v3.13.0

chore(*): release 3.13.0 (#243)

Features:
 - use persistent data structures, to improve performance
   of (module) docstrings (#241)
 - cache constructed `simp_lemma` objects (#234)
 - support `local attribute [-instance]` (#240)
 - show goal after `;` (#239)
 - `==`: compare id (#238)
 - mark deps of fixed as fixed (#237)

Changes:
 - Most of `library/init/algebra/*` has been deleted,
   as part of moving the algebraic hierarchy to mathlib (#229)