Merge pull request #92 from kallisti-dev/fix/docs-variables-typo

Fix typo in docs/variables.md

docs/variables.md

@@ -8,7 +8,7 @@ data:
 
 Cobalt makes a variety of data available as Liquid variables.
 
-This is can be helpful for:
+This can be helpful for:
 - Theming
 - Easier maintenance for only having one place to update things