Add pivot data selector

[simeonoff]

Closes #

Additional information (check all that apply):

• Bug fix
• New functionality
• Documentation
• Demos
• CI/CD

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• All relevant tags have been applied to this PR
• This PR includes unit tests covering all the new code (test guidelines)
• This PR includes API docs for newly added methods/properties (api docs guidelines)
• This PR includes feature/README.MD updates for the feature docs
• This PR includes general feature table updates in the root README.MD
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• This PR contains breaking changes
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• This PR includes behavioral changes and the feature specification has been updated with them

[3phase]

Edit: both of the issues that were logged by me, are logged separately (#11050 and #11051).

The IPivotConfiguration does not require the filters-property and defaults to null if it's not present, so the case when there's no filters in the configuration should be handled in order to avoid the error below.

[3phase]

When trying to drag and drop chips, the viewport would scroll down and eventually hide all contents above the grid. In the particular sample scenario, it's the navbar on top of page, making it unable to revive.
Edit: might be similar to the third issue that Maya has logged

[dkamburov]

LGTM, I'm only adding few minor comments.

[skrustev]

You can use the IgxDrag/IgxDrop data property to store the element ID as well like the panel type on dropped instead of accessing the native element.

PS: Might help with the dragging of chips between pivot data selector and drop areas inside the pivot grid

[simeonoff]

I already use the data property on the Drag directive for other purposes. Also, we've decided that we don't want to drag elements between the grid and the pivot data selector.