Add irc-client.0.1.2

Signed-off-by: John Else <john.else@citrix.com>
Restrict to ocaml >= 4.00.1

Signed-off-by: John Else <john.else@citrix.com>
Merge pull request #1424 from johnelse/irc-client.0.1.2

Add irc-client.0.1.2