Fix for coinurl

- The function ajax() was sending to the host window.location.host even if
the function was called with another host in the URL.
- The function $.get() was appending a '?' to the URL of the request even
if there was no data to send using GET. This could possibly lead some
Node.JS websites which did not expect GET parameters to return an error.
- Added the function $.toDOM() allowing to parse a raw HTML document into a DOM
document.
- Coinurl now works with Ghostery and other anti-tracking tools, it works on subdomains (bit.cur.lv, etc.), with custom links, also it is faster.

Example links:
http://cur.lv/8wzpa
http://coinurl.com/8wzpa (actually works even if coinurl links are 'incorrect links')
http://bit.cur.lv/frvgfdf-gdfg451dfg