Enable vale for prose linting (#3)

* Enable vale in CI

* Add vale config

* Tweak vale

* Update config

* Update .gitignore

* Switch back

* Rename CI

* Add badges

* Tidy up CI

* Change image

* Configure vale

* Delint

* Update README

.github/styles/proselint/Typography.yml

@@ -0,0 +1,11 @@
+extends: substitution
+message: Consider using the '%s' symbol instead of '%s'.
+level: error
+nonword: true
+swap:
+  '\.\.\.': …
+  '\([cC]\)': ©
+  '\(TM\)': ™
+  '\(tm\)': ™
+  '\([rR]\)': ®
+  '[0-9]+ ?x ?[0-9]+': ×