Change teachers' names appearance to use ellipses in various places

Every instance of a teachers list currently found was replaced with a single-line display separated by commas and truncated to the nearest element. This change affects 1) detailed view in Grades [issue #41 (closed)] 2) recent grades in Dashboard [issue #37 (closed)] 3) history view in Requests [issue #59 (closed)]

This further affects 2) by grouping the icon and text as one element, then having the two icon-text pairs be inline, properly centered, spaced and then ellipsed.

Normal view:

On-Hover: