Fixes ipython printing extension

This fixes two things.

First, the extension had to be reloaded to import the extension.
Fixes issue #3619

Second, this has been broken since IPython moved IPython.zmq to
IPython.kernel.zmq. This fixes this. Note, there are some git
versions of IPython where this will still break, but it should work
for all stable releases and will work for the current git version.
Remove checks that module is loaded
Remove IPython sniffing

Removes checks on whether or not one is in the qtconsole or notebook
before setting the unicode and latex once it is verified that your in
any IPython instance.
Add tests for ipythonprinting extension

Adds tests for the loading of the printing extension for IPython. This
only tests the plain text output, this could also be used to test
whether or not latex is enabled, png's are created, etc.
Make ipythonprinting test more robust
Merge pull request #1853 from flacjacket/ipython_printing_fix

Fixes ipython printing extension



This fixes two things.

First, the extension had to be reloaded to import the extension. Fixes issue #3619 [1].

Second, this has been broken since IPython moved IPython.zmq to IPython.kernel.zmq. This PR fixes this. Note, there are some git versions of IPython where this will still break (between moving the zmq module and changing the version to 1.0.dev), but it should work for all stable releases and will work for the current git version. The versions that won't work are between 1/29 [2] and 2/15 [3]. This was brought up in #1757.

[1] https://code.google.com/p/sympy/issues/detail?id=3619
[2] ipython/ipython@37f3225
[3] ipython/ipython#2927