Mention 8.20 in DOC.md and INSTALL.md (#1121)

DOC.md

@@ -2,15 +2,15 @@
 
 ## Branches and compatibility
 
-**tl;dr** You should do your PRs against [coq-8.18](https://github.com/MetaCoq/metacoq/tree/coq-8.16).
+**tl;dr** You should do your PRs against [coq-8.20](https://github.com/MetaCoq/metacoq/tree/coq-8.20).
 
 Coq's kernel API is not stable yet, and changes there are reflected in MetaCoq's reified structures,
 so we do not ensure any compatibility from version to version. There is one branch for each Coq version.
 
 The *main branch* or *current branch* is the one which appers when you go on
 [https://github.com/MetaCoq/metacoq](https://github.com/MetaCoq/metacoq).
 Currently (unless you are reading the README of an outdated branch),
-it is the [coq-8.16](https://github.com/MetaCoq/metacoq/tree/coq-8.16).
+it is the [coq-8.20](https://github.com/MetaCoq/metacoq/tree/coq-8.20).
 You should use it both for usage of MetaCoq and development of MetaCoq.
 
 The [main](https://github.com/MetaCoq/metacoq/tree/main) branch is following Coq's master
@@ -21,10 +21,6 @@ stable release of Coq.
 <!-- gets backports from `coq-8.11` when possible. Both `coq-8.11` and `coq-8.10` have associated -->
 <!-- "alpha"-quality `opam` packages. -->
 
-The branches [coq-8.17](https://github.com/MetaCoq/metacoq/tree/coq-8.17) and [coq-8.18](https://github.com/MetaCoq/metacoq/tree/coq-8.18) are being kept in sync.
-The branches [coq-8.6](https://github.com/MetaCoq/metacoq/tree/coq-8.6) to [coq-8.15](https://github.com/MetaCoq/metacoq/tree/coq-8.16) are frozen.
-
-
 ## Program and Equations
 
 MetaCoq relies on `Program` and `Equations` plugins, however try to avoid `Program` as it
@@ -89,7 +85,7 @@ a fresh level when `MetaCoq Strict Unquote Universe Mode` is off.
 
 ## Dependency graph between files
 
-Generated on 2022/07/01, sources [there](https://github.com/MetaCoq/metacoq/tree/coq-8.16/dependency-graph).
+Generated on 2022/07/01, sources [there](https://github.com/MetaCoq/metacoq/tree/coq-8.20/dependency-graph).
 
 <center>
 <img src="https://raw.githubusercontent.com/MetaCoq/metacoq.github.io/master/assets/depgraph-2022-07-01.png"
@@ -104,6 +100,6 @@ The file `README.md` in https://github.com/MetaCoq/metacoq.github.io is supposed
 `README.md` in [https://github.com/MetaCoq/metacoq/](https://github.com/MetaCoq/metacoq/).
 
 That's why we can't use relative links and have to use absolute ones.
-E.g. [INSTALL.md](https://github.com/MetaCoq/metacoq/tree/coq-8.16/INSTALL.md) and not [INSTALL.md](INSTALL.md).
+E.g. [INSTALL.md](https://github.com/MetaCoq/metacoq/tree/coq-8.20/INSTALL.md) and not [INSTALL.md](INSTALL.md).
 
 Thus, when switching to a new default branch, we have to search and replace the old branch with the new one.

INSTALL.md

@@ -66,10 +66,10 @@ to have a dedicated `opam` switch (see below).
 To get the source code:
 
     # git clone https://github.com/MetaCoq/metacoq.git
-    # git checkout -b coq-8.18 origin/coq-8.18
+    # git checkout -b coq-8.20 origin/coq-8.20
     # git status
 
-This checks that you are indeed on the `coq-8.18` branch.
+This checks that you are indeed on the `coq-8.20` branch.
 
 ### Setting up an `opam` switch
 
@@ -78,10 +78,10 @@ To setup a fresh `opam` installation, you might want to create a
 one yet. You need to use **opam 2** to obtain the right version of
 `Equations`.
 
-    # opam switch create coq.8.18 --packages="ocaml-variants.4.14.0+options,ocaml-option-flambda"
+    # opam switch create coq.8.20 --packages="ocaml-variants.4.14.0+options,ocaml-option-flambda"
     # eval $(opam env)
 
-This creates the `coq.8.18` switch which initially contains only the
+This creates the `coq.8.20` switch which initially contains only the
 basic `OCaml` `4.13.1` compiler with the `flambda` option enabled,
 and puts you in the right environment (check with `ocamlc -v`).