use io to support python2+3; some minor other cleanup (#211)

.gitignore

@@ -1,12 +1,19 @@
-domdiv/fonts/*.otf
-domdiv/fonts/*.ttf
 *.pdf
 *.pyc
-generated
 *.egg-info
 build
 dist
 *~
+.DS_Store
+.eggs
+.pytest_cache
+.python-version
+
+.vscode
+
+generated
+domdiv/fonts/*.otf
+domdiv/fonts/*.ttf
 dominion_dividers.pdf
 dominion_dividers.png
-.DS_Store
+tools/card_db