Description

This pull request makes the timeline:

• Center the timeline to the current time if snapped and the current time went out of view range
• Positionate the time view range with the current time on the left (start time) in case of forward/backward animation ( at is goes during the animation).

Note: the 2nd point places the point at the start following the animation strategy, instead the 1st point simply center the point.

Issues

• Fix If guide layer is active, follow the cursor when snap #3395
  Please check if the PR fulfills these requirements
• The commit message follows our guidelines: https://github.com/geosolutions-it/MapStore2/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (check one with "x", remove the others)

• Feature

What is the current behavior? (You can also link to an open issue here)

• When the user click, the cursor may disappear from the viewport without any feedback, in case it snaps out of the current view range
• If the user click on forward/backward moving the current time out of the current view range, the cursor disappears out (if you're not animating)

What is the new behavior?
The timeline centers to the current time, if snapped out of the view range

• When the user click on the forward/backward buttons, the timeline moves to include the currentTime
• If the user click on forward/backward the timeline always follow the cursor if it goes out of the view range

Does this PR introduce a breaking change? (check one with "x", remove the other)

• No

Other information:

This PR contains also some unit tests to cover timeline epics and playback settings and so increase test coverage.