Adds an "Index" button on post pages, allowing you to return to a search starting from the ID of the current post you're on
Adds a handy index button to the post view page, allowing you to return to a search while retaining your place in it. The ID of the post you're on will be appended to the end of your search, starting it from where you left off.
It will attempt to substitute an existing ID at the end of a search, so that you can use this continuously throughout one search session. I was able to get this to perform well with extra terms added after the ID in a search, but I'm sure someone will find a way to break it.
