Select clearnet tab by default

[rugk]

Otherwise "no tab" is selected by default which not only looks ugly, but causes problems if you have a special clearnet value (e.g. with a subdir or similar things)...

[rugk]

To clarify the "causes problems": Without this fix img.bi always assumes you have installed it in the root dir of the server (aka example.com/...), but when you have not, only a click on "Clearnet" shows the correct url, e.g. example.com/mysubdir/....