libres3: use opam-built ocamlnet instead of embedded

ocamlnet 3.7.4 is out now, use that instead of the embedded version.
Merge pull request #2057 from diml/master

optcomp 1.6
[Frama-C] version Neon 20140301 with ocamlgraph 1.8.5
Merge pull request #2058 from bobot/framac

[Frama-C] version Neon 20140301 with ocamlgraph 1.8.5
Merge pull request #2056 from edwintorok/libres3-fix

libres3: use opam-built ocamlnet instead of embedded
Fix Travis 4.02 compiler switch
Merge pull request #2060 from avsm/master

Fix Travis 4.02 compiler switch
Removed 'binary'

  'ocplib-endian' should be used instead
Added 'alberto-0.2'

  'alberto-0.1' was removed because it depends on 'binary-0.1' which
  isn't present in OPAM as of ae1e287
core 111.13.00-rc1
Updated checksum -- appears the archive has changed at Github, despite
no code changes.
Sync latest compiler pull requests
Merge pull request #2064 from bactrian/sync-prs-1400022001

Sync OCaml compiler PRs
Merge pull request #2063 from johnwhitington/master

Updated checksum -- appears the archive has changed at Github
Merge pull request #2061 from superbobry/master

Removed 'binary' and upgraded 'aberto'
fix async checksum due to async_core->async_kernel rename
Fix Mirage package checksums due to upstream repository renaming
fix xen-block-driver checksums due to upstream repository renaming
fix ocaml-indent checksum, verified from package contents
Fix shared memory ring checksum