Added two more properties for responsive images

Signed-off-by: Ralf Koller <r.koller@gmail.com>
Removal of matchmedia.js, jQuery and  pictureserve.js and some cosmetics

Signed-off-by: Ralf Koller <r.koller@gmail.com>
Readme cleanup

Signed-off-by: Ralf Koller <r.koller@gmail.com>
Rough migration of pictureserve.js from jQuery to JS - Part I

Signed-off-by: Ralf Koller <r.koller@gmail.com>