Change namespace Exception name.

[quentin389]

I don't wanna know who wrote that code:

use \Exception as BaseException;
class Exception extends BaseException
{}

but that's some really terrible piece of code.

I'm gonna change the in-namespace exception to something like BrowscapException, and update all the throws.
That can break someones code, but tbh it's a fair price for not keeping this monster alive.

[ntvsx193]

Pull request #42