clearer code for radio
Merge pull request #438 from bem/radio-imp

clearer code for radio
radio-group: remove redundant code
Merge pull request #450 from bem/radio-imp

radio-group: remove redundant code
menu: double shift on each keydown in IE (close #453)
Merge pull request #454 from bem/issues/453@v2

menu: double shift on each keydown in IE (close #453)
button: wrong behaviour on _focused mod (close #455)
Merge pull request #456 from bem/issues/455@v2

button: wrong behaviour on _focused mod in IE (close #455)
attach: Fix BH. Closes #435