INSTALL.adoc: explain why configure looks for the curses library.
INSTALL.adoc: explain why configure looks for the curses library.

Hint: it is used in the toplevel to highlight errors using something nicer
than a bunch of (slightly-misaligned) '^' on a new line.

NB: $curseslibs ends up in $BYTECCLIBS and we probably link against curses
in the bytecode runtime while we only need it for the toplevel.

gerdstolpmann/ocaml,gerdstolpmann/ocaml,yunxing/ocaml,yunxing/ocaml,msprotz/ocaml,msprotz/ocaml,gerdstolpmann/ocaml,yunxing/ocaml,yunxing/ocaml,yunxing/ocaml,gerdstolpmann/ocaml,msprotz/ocaml,gerdstolpmann/ocaml,msprotz/ocaml,msprotz/ocaml