add following config method modal, fix some related

* added modal window with following config (now there is choosing of private or public method only) which appears when any _follow_ button was clicked (at profile modal window, buttons on mini profile summary from quick search results and who-to-follow tab on both `index.html` and `following.html` pages)
* fixed showing and switching current method of following on `following.html` page

it is that part of work which must be done before we start to play with other stuff from the [list](http://twister.net.co/?p=415).