15.1: Tooltip basic example
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**Primary Actor**: User

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

**Goal**: Show user Basic Tooltips functionality  

Main success scenario:
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1. User opens Tooltip demo page
2. User clicks on Basic sub-menu
3. User see button "Simple demo"  
4. When user on hover on "Simple demo" button, then tooltip-container shown on the top of button with specific text
5. When user moves the mouse cursor away of tooltip-button, then tooltip-container disappeared

Variations:
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2*. User scroll to Basic sub-menu