feat(Popup): add pinned and popperModifiers prop

[layershifter]

Fixes #3615.

pinned

Will stop flipping of opened Popup.

popperModifiers

We can't map all PopperJS modifiers to component's props, so it will be better to just export them to allow customize them.

Restore rending children in ComponentExample

I just noticed that we're are missing helpful descriptions in docs:

Fixed 💥

[codecov-io]

Codecov Report

Merging #3654 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master    #3654   +/-   ##
=======================================
  Coverage   99.81%   99.81%           
=======================================
  Files         174      174           
  Lines        2749     2749           
=======================================
  Hits         2744     2744           
  Misses          5        5

Impacted Files	Coverage Δ
src/modules/Popup/Popup.js	98.24% <100%> (ø)	⬆️

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[RRSR]

Even after adding pinned the popup move up if squeezed

<StyledPopup basic content={<SomeKindaList />} flowing hoverable onOpen={props.p1} onClose={props.p2} open={props.p3} position='bottom right' trigger={( <StyledLinkMenuItem isOpenPopup={props.p1}> .......... </StyledLinkMenuItem> )} offset='0, -10' pinned />

So if I decrease the window size the popup moves up. How to fix the same.