2.5: Buttons Radio example
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**Primary Actor**: User

**Scope**: Ngx-bootstrap DEMO / BS version 3&4

**Goal**: Show user radio-buttons usage example with checked/unchecked states

Main success scenario:
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1. User opens Buttons demo page
2. User clicks on Radio sub-menu
3. User see 2 button-groups (primary and success), contain of 3 parts(labels)
4. By default, in each group, 1st button is inactive, 2d - active and 3d - inactive
5. User able to click on each button
6. When user clicks on the inactive button, it become active and other buttons in this group become inactive
7. Click on N(Left, Middle, Right) button in A group make all N buttons active in all groups

Variations:
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2*. User scrolls to Radio sub-menu