Feature/fade on top scale num columns

[UnattendedFlight]

Added flatlist numColumns functionality to VegaScrollList + config parameters

[UnattendedFlight]

Reason for pull request:

I noticed that when more columns was added using numColumns, the actual columns were never taken into account for the animations. Only the first item would animate, then scrolling further down. Things got messy.

As such, I propose these minimal changes to allow for animating flatlists with more than one column.

Also additionally, there was a lack of configuration capabilities, so alongside numColumns feature, I've also added 2 more parameters.

fadeOutTop (boolean)  - decides whether the topmost items should fade out when scrolling further
scaleOutMin (number) - the scale number to animate to when the scale animation is applied.