Added an option to open the link in same window

[bittenbytailfly]

I get that this is largely supposed to be used for advertising, but I recently wanted to use this to change a background on a web page and create a peelback illusion. This meant I didn't want it opening in a new window.

I've made a very quick change to make this optional, but have defaulted it to set the target to "_blank" for backward compatibility.