Peony version 1.0.0

I finally released the 1.0.0 version of Peony.

A lot of things changed everywhere as I tried to create tests for the
main module (peony.commands is still untested when you run the tests) so
Peony is now a bit more reliable.

I tried to keep most existing codes working as expected.
The most problematic change that was made since v0.9.3.1 is that I
removed the auto_convert and max_sizes parameters of
PeonyClient.upload_media() (the original functions that were called
when you used this option are in examples/upload.py).

I just thought that it was actually unnecessary for this feature to be
in Peony and that upload_media() should just send the file that is
given as an argument.

Some nice features have been added and should now be in the
documentation:

• Accessing the text attribute of a tweet should get the full text of
  the tweet if the text item is truncated
• upload_media() accepts the media_type and media_category arguments if
  you want to manually specify these parameters for some reason
• peony.events.default can be used to match any event that wasn't
  matched by any other event handler
• Custom events can now be easily created using the peony.events
  decorator