Use the usage of print in the examples.

To fix an error when installing chaussette.
Update index.rst

previous link gives 404.
Merge pull request #58 from mgaitan/patch-1

replace link to circus's sockets section
Allowing additional commandline arguments which are ignored by chaussette.
Merge pull request #60 from max0d41/master

Allowing additional commandline arguments which are ignored by chaussette