File or a list of files to be included
Optional callback: callbackFunction to be called when the inclusion is complete
Optional isolate: booleanIndicates whether the script code should be loaded as isolated, so that its global variables don't interfere with other scripts (useful for custom scripts)
Optional local: stringOptional reload: booleanrequirejs
Includes a JS file. Uses window.eval(), so that the content is executed in the 'window' context and also immediatelly available for the following code. '.js' extension isn't necessary and is added if missing. Duplicates (including those from <script> tag) are automatically ignored.