* downloadPDF is a function downloads a pdf from the internet through a URL
* @param url is the URL you want to download from
* @param filename is by default set to tempContract.pdf, but can be set manually if another name or location for file is prefered
* downloadPDF is a function that downloads a pdf from the internet through a URL
* @param url is the URL you want to download from and the URL must end with .pdf
* @param filename is by default set to tempContract.pdf and stored in the utils-folder. another name can be set if prefered. The new filename should have the .pdf extension