irclib: Make SASL messages easier to understand

The logs are meant to be understandable by humans, and not everyone
might know AUTHENTICATE is a SASL command.

[ci skip]
irclib: Remove some useless SASL debug messages
irclib: Add support for additional SASL numerics
CONTRIBUTING.md: use proper language && fix links.

The links went to supybot.fr.cr where the website moved away long time ago.
README.md: Sanify topis & fix IRC links.

IRC links were going to irc.freenode.net which is CNAME for
chat.freenode.net .
Merge pull request #586 from nyuszika7h/update-sasl

Some updates to SASL
Merge pull request #587 from Mkaysi/readme-contributing

Update CONTRIBUTING.md and README.md.
Fix neutral pronouns.
Fix one occurence missing from previous commit.
httpserver: Fix crash if supybot.servers.http.favicon has not been set.
.travis.yml: add Python 3.4.

According to https://github.com/travis-ci/travis-ci/issues/1989 Travis
will get Python versions from
https://launchpad.net/~fkrull/+archive/deadsnakes
and that PPA has python3.4 so it should be installed to them soon.

Feel free to not merge this until it has happened.
Merge pull request #590 from Mkaysi/travis

.travis.yml: add Python 3.4.
Revert ".travis.yml: add Python 3.4."

This reverts commit d84f6b48344bce0c3f225d8d695680ae86bb6ff6.
Add 'reply_env' attribute to IrcMsg.
Copy the reply_env when copying an IrcMsg object.
Fix previous commit.
Fix utils.gen.safeEval to work with instances of ast.NameConstant (introduced in Pythn 3.4).
cdb: Remove debug output.
.mailmap: fix Mikaela's name and email addresses.
Merge pull request #592 from Mkaysi/mailmap

Mailmap: fix my name and email addresses for git.