Previously the OCaml compiler was only required if building from git
but was at least theoretically optional if building from tarballs
(although this was never tested). Since we want to write parts of the
daemon in OCaml, this makes OCaml required for all builds.
Note that the ‘--disable-ocaml’ option remains, but it now only
disables OCaml bindings and OCaml virt tools. Using this option does
not disable the OCaml compiler requirement.
Also note that ‘HAVE_OCAML’ changes meaning slightly, so it now means
"build OCaml bindings and tools" (analogous to ‘HAVE_PERL’ and
others). The generator, daemon [in a future commit], and some utility
libraries needed by the generator or daemon do not test for this macro
because we can assume OCaml compiler availability.
The new module ‘Std_utils’ contains only functions which are pure
OCaml and depend only on the OCaml stdlib. Therefore these functions
may be used by the generator.
The new module is moved to ‘common/mlstdutils’.
This also removes the "<stdlib>" hack, and the code which copied the
library around.
Also ‘Guestfs_config’, ‘Libdir’ and ‘StringMap’ modules are moved
since these are essentially the same.
The bulk of this change is just updating files which use
‘open Common_utils’ to add ‘open Std_utils’ where necessary.