Search.jsx — some key presses aren't working as intended

[perpetualgrimace]

• Key presses are currently scoped to the Search input field.
• Hitting up/down keys to shift focus onto different links no longer works. 😬
• When tabbing through links, hitting escape doesn't fire this.clearSearch()
• Potential enhancement: left/right keys shift focus to the first link in the previous/next list?

[jhmullen]

I am closing #400 as a duplicate of this because this is a better description of the problem

[alexandersimoes]

These enhancements are all related to keyboard navigation improvements for the search box.