ua: add support for ie11+

Hey!
IE since 11 version doesn't match previous regexp. Moreover, it simulates useragent like FF 11.
```
IE 11: "Mozilla/5.0 (Windows NT 6.3; Trident/7.0; .NET4.0E; .NET4.0C; rv:11.0) like Gecko"
FF 35: "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:35.0) Gecko/20100101 Firefox/35.0" 
```
Thus, our current implementation of `ua` recognizes IE 11 as FF 11.

//cc @dfilatov @narqo 
Another strange thing I have noticed is "IE11 for the desktop on 64-bit Windows 8.1 with enterprise mode enabled" (WAT?) from [User-agent string changes](http://msdn.microsoft.com/en-us/library/ie/hh869301(v=vs.85).aspx) of MSDN:

~~~
Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; Tablet PC 2.0)
~~~

It has "trident" token, but there is no "rv" part :( 

The same shit is with several other IE 11 x64 from the article above.