Fix some missing punctuation

Author: bbatsov

README.md

@@ -1625,14 +1625,14 @@ the docstring at various places.
 (defn frobnitz
  "This function does a frobnitz.
  It will do gnorwatz to achieve this, but only under certain
- cricumstances"
+ cricumstances."
  []
  ...)
 
 # bad
 (defn frobnitz
  "This function does a frobnitz. It will do gnorwatz to
- achieve this, but only under certain cricumstances"
+ achieve this, but only under certain cricumstances."
  []
  ...)
 ```