add libexpat as a depext of all lablgtk versions

This continue f65f8eaf7415a06ec13277db33be0d08625ac28d
Add version constraint on OMD for Lambdoc
Add google-drive-ocamlfuse 0.5.9
Add OSX homebrew dependencies (sqlite and osxfuse)
Fix OSX depexts
Remove OSX sqlite depext
Remove OSX depexts
Add xapi-stdext.0.12.0 (with OS X compatibility)

Signed-off-by: David Scott <dave.scott@citrix.com>
Merge pull request #2763 from samoht/master

add libexpat as a depext of all lablgtk versions
mirage-unix: fix remove instructions for version 0.9.1 to 0.9.7
add ocaml-imap 0.20.0
Merge pull request #2767 from djs55/xapi-stdext

Add xapi-stdext.0.12.0 (with OS X compatibility)
Merge pull request #2770 from planar/mirage-unix-remove

mirage-unix: fix remove instructions for version 0.9.1 to 0.9.7
ocamlnet needs camlp4 to use ocaml-pcre
ocaml-http requires camlp4
Add SLAP 0.2.0
Merge pull request #2773 from akabe/master

Add SLAP 0.2.0
Merge pull request #2772 from planar/ocaml-http-camlp4

ocaml-http requires camlp4
Merge pull request #2765 from nojb/master

add ocaml-imap 0.20.0
update to menhir.20140422

closes #2774