如果有人仍然想知道该怎么做:

If someone still want to know how to do that:

require.config({
    paths: {
        'jquery' : (function(){
            if( MODE == 'DEV' ){
                return 'jquery';
            }else{
                return 'jquery.min'
            }
        })()
    }
});

此功能是自调用匿名功能.它会在定义位置立即调用.

This function is self invoking anonymous function. It invokes immediately in the definition place.