Fixed IE base href bug

As I said this PR fix the problems with IE. Please @leoyuholo mind that the links here are working for an HTTP url (so no file:// url) and that the folder JSEncrypt must be in the root public directory of the website (so http://localhost/jsencrypt/ works, http://localhost/example/jsencrypt/ doesn't.).
@travist as you can see I played a little bit with the links to check whether IE works or not, if you think this is too much untidy i can squash commits. The bin/jsencrypt.js commit is instead the result of updating my fork with your.
When you are ok with this PR you can merge master in gh-pages ;-)