Answers for "how to import one js file to the other"

include other js files in a js file

document.writeln("<script type='text/javascript' src='Script1.js'></script>");
document.writeln("<script type='text/javascript' src='Script2.js'></script>");

javascript include a js file from another

// jQuery
$.getScript('/path/to/imported/script.js', function()
{
    // script is now loaded and executed.
    // put your dependent JS here.
});