Search results navigation interaction correction

#### Purpose

Fix small but not comfortable issues in search results navigation.

#### Modifications

Debug. Some hours of debug. As result some places were improved.

Were added functions to find next or previous *visible* category.

#### Additional references

For the most serious issues were created next tasks:

* [MAGN-5722](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-5722) DUI: Do not navigate for closed category members
* [MAGN-5723](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-5723) DUI: Navigation should start from TopResult if nothing selected 
* [MAGN-5724](http://adsk-oss.myjetbrains.com/youtrack/issue/MAGN-5724) DUI: If selected member is in just closed category, next arrow button should start navigation from TopResult 

#### Reviewers

@Benglin, please, take a look.