Horizontal scroll

[underfisk]

• Nested headers might not work due to height being fixed to 100 but autoHeight enabled, this needs to be tested
• Horizontal scroll is broken due to the fact its on comment and needs to be re-created for only scrollLeft
• Main grid need to use the onScroll from horizontalScroll handler to detect if scrollLeft is changing also in there, we compare the values

[RitaBeloMoreira]

@VeraRibeiro After scroll sync is this issue fixed?