Update leiningen to 2.3.0.

Unfortunately, leiningen will now pull in some dependencies via maven (via http) on `lein version' so the test at the end of builder.sh failed. This is okay because leiningen is used only as a interactive tool and no other package in Nixpkgs depends on it.

Signed-off-by: Moritz Ulrich <moritz@tarn-vedra.de>
Add HTTPS support to Midori
torbutton: package version 1.6.1
unclutter: add to channel
add libvisual 0.4.0
Merge pull request #819 from iyzsong/libvisual

add libvisual 0.4.0
Merge pull request #817 from offlinehacker/pythonPackages.carbon

pythonPackages: fix carbon, move dependecies to propagated build inputs
Merge pull request #816 from offlinehacker/pycurl2

Add pycurl2, a Python interface to libcurl
Merge pull request #812 from the-kenny/leiningen-2.3.0

Update leiningen to 2.3.0.
leiningen: fix hash
pythonPackages: fix graphite_web, make it usable