Accessibility: side navbar

[gaurav5430]

These are some of the accessibility issues i have identified on the side nav bar, with some quick solutions (may not be the best):

• there is no indication that this is a menu or nav - can use nav element
• there is no indication for the current active item for the screenreader user - can use aria-current="true"
• keyboard users can focus on the next item using tab, but can't activate it using space / Enter - can use button instead of a div with onClick
• there is a visual change on mouse hover but not on keyboard focus (although the tooltip gets shown, which is an indication that the focus has changed) - apply the same styles as hover

[saumeya]

@gaurav5430 can you share screenshots of the change, thanks!