These options let JSHint know about some pre-defined global variables.
+Note: the JSHint project is no longer accepting new
+library-specific "environment" options. Please use the
+globals configuration option to manage globally-defined
+bindings. (JavaScript libraries come and go, and even the most popular and
+stable are subject to change over time. Supporting multiple versions
+concurrently increases maintenance burden and introduces coordination issues
+that are best avoided by allowing consumers to explicitly manage custom rules
+in their own projects' configurations. Those libraries that are currently
+supported are maintained only to honor commitments made before this change in
+policy.)