add backout

• removed strict_url_change option
• added backout option

backout

when you navigate within the same page multiple times and thus push the same history entry for that same page multiple times, you'd also have to go back multiple times to leave that page

this option is a QOL change, that will back out for you.

example: if you have a kitchen page with "lights" and "blinds" and navigate to lights and blinds from within that page multiple times, pressing back with backout will immediately leave the kitchen page