"optimize" the lexer
Merge pull request #531 from oandrieu/fix-lexer

"optimize" the lexer
Correcting some typos in OPAM diagnostics and error messages

Signed-off-by: Thomas Gazagnaire <thomas@gazagnaire.org>
Add CONTRIBUTORS file
Update CHANGES
Update the AUTHORS file
Prepare the release
Update the doc
Fix tests
Full OS name for all BSD variants
Fix #540
Update CHANGES
Fix stupid typo
Update CHANGES
Remove '-n' command-line ambiguities on opam-init (need to fully write --no-checksum now)

Fix #539
Udpate CHANGES
OpamClient.SafeAPI can now be used in a toplevel.

Fix #544
Update CHANGES
Improve the error message when using a switch which has not yet been installed.

Fix #542
Clean-ups in the switch code.

This can help #542

We now export and read OPAMSWITCH to be able to run OPAM itself inside a different switch.