Add basic INSTALL instructions

INSTALL

+cool solver installation notes
+==============================
+
+Dependencies
+------------
+Install ocaml include files, minisat include files. Place them in the include
+directory (e.g. /usr/include, /usr/lib/ocaml, or .) or adjust the search path
+via the INCS setting in the Makefile.
+
+Build
+-----
+Type:
+
+  make
+
+Installation
+------------
+Not possible yet.
+
+// vim: ft=asciidoc tw=80