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 
Also, why do we need use pipe symbol after `rv:([\w.]+)` ?