'opam install bson' works, but 'opam install js_of_ocaml bson' fails because 'deriving' is needed when 'js_of_ocaml' is present, but both are listed as optional dependencies. Solution: move 'deriving' from the list of optional to strong dependencies.
+dns.0.10.0
Merge pull request #2524 from avsm/dns.0.10.0

+dns.0.10.0
fix non-portable use of sed's -i option
jsoo.2.4.1
Fix dose uninstall instructions
tplib: remove spurious ocamlbuild options from Makefile
Merge pull request #2532 from hhugo/jsoo241

Minor release of js_of_ocaml
Merge pull request #2533 from AltGr/rm-dose

Fix dose uninstall instructions
Merge pull request #2530 from planar/ocp-ocamlres-sed-problem

fix non-portable use of sed's -i option
lablgtk: add missing dependency on camlp4
Sync latest compiler pull requests
Merge pull request #2538 from planar/lablgtk-missing-dep

lablgtk: add missing dependency on camlp4
Merge pull request #2539 from bactrian/sync-prs-1409266801

Sync OCaml compiler PRs
Merge pull request #2537 from Chris00/master

+fftw3 v0.7.1
Restrict custom_printf to <4.02.0 OCaml where not supported
extlib depends on camlp4
Merge pull request #2536 from planar/tplib-makefile-fix

tplib: remove spurious ocamlbuild options from Makefile
Add missing depext on curses
Add remove target for atdgen

This is to fix an issue when I was upgrading opam from
opam 1.1.2 to opam 1.2~beta4. See #2535.