Bug correction about the shrinkToFit feature

This commit correct a bug that used the full page height instead of the viewport height, causing strange behavior in very long webpages.

There's also some optimizations regarding how the shrinkPadding value is used to define the modal size, including a new function to remove duplicated code when resizing the modal.

My code editor didn't like the fact that the file was in a ISO-something format so I converted it to UTF-8. (Looks like it was the only file that wasn't UTF-8 in the project)

And finally I added some informations about how to minify the javascript file, and added the "preserve" keyword at the top to get the same result (that is to say, as close as I could) as before with the last Google Closure Compiler version.