Add pkgs/applications/science/logic/hol_light
and pkgs/applications/science/emacs-modes/hol_light
Some functionalities of HOL Light requires the compiled sources of
OCaml. For now we provide a new package ocaml_with_sources. After
this shuold be merged with the current version of OCaml already
present in nixpkgs.
svn path=/nixpkgs/trunk/; revision=20008
