Python 3.4 support

[pdonorio]

Hi,
Python 3.4 seems not supported as I read stated:

Syntax-highlighting, declarative and composable pretty printer for Python 3.5+

Is there any particular reason behind it?
I really like your project and willing to help adding that support
since we have to support Python 3.4+ in all of our projects and this library could break our compatibility.

Thanks for your work

[tommikaikkonen]

Thanks! No particular reason, on Python 3 I've only worked with 3.5 and 3.6, so initially I wrote the library to support just 3.6. I recently added support for 3.5. With that change, the test suite is ran against multiple Python versions (3.6 and 3.5). 3.4 would be easy to add there from the tox config.

I think the test coverage is pretty good, so I'll gladly accept a PR that supports 3.4 and passes tests on all 3.4, 3.5 and 3.6 on the CI I've set up on this repo.