decaffeinate: add page (#2228)

pages/common/decaffeinate.md

@@ -0,0 +1,19 @@
+# decaffeinate
+
+> Move your CoffeeScript source to modern JavaScript.
+
+- Convert a CoffeeScript file to JavaScript:
+
+`decaffeinate {{path/to/file.coffee}}`
+
+- Convert a CoffeeScript v2 file to JavaScript:
+
+`decaffeinate --use-cs2 {{path/to/file.coffee}}`
+
+- Convert require and module.exports to import and export:
+
+`decaffeinate --use-js-modules {{path/to/file.coffee}}`
+
+- Convert a CoffeeScript, allowing named exports:
+
+`decaffeinate --loose-js-modules {{path/to/file.coffee}}`