Fix AttributeError when closing card creation dialog with Kanji field selected

Although the error disappeared, please, @cayennes, check if the fix is correct as I'm not a Python programmer.

Thanks
Merge pull request #33 from LucasEasedUp/patch-1

Fix AttributeError when canceling card creation with Kanji field focused
Parallel tests in CircleCI

Using pytest-circleci

Mainly just-because; the tests are quite short and setup takes longer.

Also switch to verbose pytest output.
Update README

- correct link for downloading generated diagrams
- better info for installing anki addon
- fixed formatting issue for running tests (not that it's really the
  best way...)
- fix a misspelling
- added a picture
Bump version for LucasEasedUp's fix
Colorize kana in anki

Now do stroke order diagrams in anki when the character consists of a single
kana.  Retains behavior of diagrams for only kanji in full sentences.

Fixes issue #20 and issue #32
Output junit.xml for circle