adding -webkit specific fix for ul spacing

Basically I have noticed some jumpiness and it comes from -webkit browsers that add margin-before, margin-after, margin-start, margin-end, padding-start css to ul elements. This removes that, but only if the element has a class of bxslider. might be better to add it via js or another way. But in ticker mode the padding-start that Chrome/Safari adds, makes the slider jump on the last slide typically. By removing that spacing, it removes the jump.