GF-60878: Specifying defaultSpotlightDown/Up on paging controls of moon.Scroller

Fixing http://jira2.lgsvl.com/browse/GF-60878

This issue is reported from SmartShare and have Q issue regarding to
this.
Reproduce:
1) Open DataGridList Sample and move focus down to items on second page.
2) Move focus to paging controls. (paging down control)
3) Press up key.
Problem:
Focus is not moving to paging up control
Expected result:
Focus is moves to paging up control
We can get this result by simply set defaultSpotlightUp/Down property on
Paging Up/Down controls.

DCO-1.1-Signed-Off-By: Kunmyon Choi <kunmyon.choi@lge.com>
Merge pull request #1120 from enyojs/GF-60878-kunmyonchoi

GF-60878: Specifying defaultSpotlightDown/Up on paging controls of moon....