Make module_type_of_size.t portable and maintainable

It's now easier to change the size of the test as the intermediate mli
files are no longer in the source code.
The test is also easier to read.

test/xref2/module_type_of_size.t/run.t

@@ -12,40 +12,16 @@ Start with a base module:
   module N : sig type t end
   module T : sig type t type u end
 
-Script to compile the modules:
-  $ ./compile.sh
-  + ocamlc -c m1.mli -bin-annot
-  + ocamlc -c m2.mli -bin-annot
-  + ocamlc -c m3.mli -bin-annot
-  + ocamlc -c m4.mli -bin-annot
-  + ocamlc -c m5.mli -bin-annot
-  + ocamlc -c m6.mli -bin-annot
-  + ocamlc -c m7.mli -bin-annot
-  + ocamlc -c m8.mli -bin-annot
-  + ocamlc -c m9.mli -bin-annot
-  + ocamlc -c m10.mli -bin-annot
-  + ocamlc -c m11.mli -bin-annot
-  + ocamlc -c m12.mli -bin-annot
-  + ocamlc -c m13.mli -bin-annot
-  + ocamlc -c m14.mli -bin-annot
-
-And one to run odoc on the files:
-  $ ./odoc.sh
-  + odoc compile -I . m1.cmti
-  + odoc compile -I . m2.cmti
-  + odoc compile -I . m3.cmti
-  + odoc compile -I . m4.cmti
-  + odoc compile -I . m5.cmti
-  + odoc compile -I . m6.cmti
-  + odoc compile -I . m7.cmti
-  + odoc compile -I . m8.cmti
-  + odoc compile -I . m9.cmti
-  + odoc compile -I . m10.cmti
-  + odoc compile -I . m11.cmti
-  + odoc compile -I . m12.cmti
-  + odoc compile -I . m13.cmti
-  + odoc compile -I . m14.cmti
+Generate a chain of `module type of`s:
 
+  $ N=14
+  $ for i in `seq 2 $N`; do echo "module type M = module type of M$((i-1)) with module N = M1.T" > m$i.mli; echo "module N : sig type t end" >> m$i.mli; done
+
+Compile the modules:
+
+  $ for i in `seq 1 $N`; do ocamlc -c "m$i.mli" -bin-annot; done
+
+  $ for i in `seq 1 $N`; do odoc compile -I . "m$i.cmti"; done
 
 None of the files really ought to be bigger than 1M!