Added upload functionality. In order to upload bigger sized-files, you must edit the php.ini file and set max upload size and post upload size to 10M or more to accomodate better quality songs/longer duration-songs. upload_max_filesize=10M, upload_max_filesize=10M, save the changes made to php.ini.Also added folders uploads where uploads made by the user will be stored. It is located in PlayMix->uploads. Also added mp3 folder where songs will be stored when uploaded.