Fixes #271

The opensearch method is now the method set in the preferences.

As before, POST by default and GET for Chrome/Chromium which doesn't
handle POST

[fix] btdigg: disable ssl check

[fix] #253

Moar engines

I didn't remove the engines files because it always could be helpful if they come back.

[fix] update yahoo engine according to the web site changes

small update of russian translation

Remove whitespace and allow autocompleter to work in sub folders

Translations update

[fix] close #197 for all engines

Some RTL fixes

- Pull the suggestions to the right in oscar
- Add `‎` to a few places to print good url
- Always LTR code display
- Order pref label and info in pref for mobile view

And add `sort` for ui languages and languages to find them more easily.

[fix] kickass engine

Close #197 perhaps not in clean way. Explanation :
In fact 301 responses are followed, except the hook is called for each HTTP response,
the first time for the HTTP 301 response then for HTTP 200 response.
Since the kickass engine excepts a real result, the engine crashes, AND the requests lib stops here.
Add a simple test at the beginning of the result function allows pass the first response and handle correctly the second response (the real one)

May be a proper way is to add this test in search.py ?

Code inside requests :
https://github.com/kennethreitz/requests/blob/53d02381e22436b6d0757eb305eb1a960f82d361/requests/sessions.py#L579
and line 591