move to 4.08 as lower bound

Author: c-cube

.github/workflows/main.yml

@@ -16,7 +16,6 @@ jobs:
           #- windows-latest
           #- macos-latest
         ocaml-compiler:
-          - 4.03.x
           - 4.08.x
           - 4.12.x
     runs-on: ${{ matrix.os }}

README.md

@@ -12,9 +12,13 @@ including:
 
 See https://c-cube.github.io/printbox/
 
+## License
+
+BSD-2-clauses
+
 ## Build
 
-Ideally, use [opam](http://opam.ocaml.org/):
+Ideally, use [opam](http://opam.ocaml.org/) with OCaml >= 4.08:
 
 ```sh non-deterministic=command
 $ opam install printbox printbox-text

printbox.opam

@@ -12,7 +12,7 @@ depends: [
   "dune" { >= "2.0" }
   "base-bytes"
   "odoc" {with-doc}
-  "ocaml" { >= "4.03" }
+  "ocaml" { >= "4.08" }
 ]
 license: "BSD-2-Clause"
 tags: [ "print" "box" "table" "tree" ]