paper-menu's bold on select styles are no longer part of Material Design

[dantman]

The bold on select styling paper-menu uses isn't anywhere in current Material Design specs. It may have been part of an earlier draft before I ever read it, but the selected styling paper-menu doesn't follow any of the patterns in the current Material Design spec. paper-menu's focus/hover behaviour is also problematic, but that's a separate bug.

Menus (see https://www.google.com/design/spec/components/menus.html) describe behaviours for dropdown menus. In general these menus do not have any selected item states. <select> type dropdowns either simply focus the current item initially or use normal styles for the current item and the secondary text colour for non-selected items. No types of other behaviours for menus suggest bolding items for any reason.

Navigation drawer lists (https://www.google.com/design/spec/patterns/navigation-drawer.html) do have a selected state behaviour. Selected items retain a normal font weight, but the text and item colour is changed to the app's primary color (or a darker version of it if there isn't enough contrast).