Use absolute paths for lib paths in utop
Use absolute paths for lib paths in utop

This makes $ jbuilder utop usable from sub directories

dra27/jbuilder,janestreet/jbuilder,rdavison/jbuilder,dra27/jbuilder,dra27/jbuilder,dra27/jbuilder,dra27/jbuilder,dra27/jbuilder,janestreet/jbuilder,janestreet/jbuilder,janestreet/jbuilder,rdavison/jbuilder,janestreet/jbuilder,janestreet/jbuilder