When in mobile mode for a page, the product name is now vertically
centered in relation to the logo, instead of being aligned to the top,
creating a nicer look.

The hamburger menu on the left is no longer hard-coded as black, but
instead will match the text color. This allows a page to have a dark
background without making the menu invisible.

Saw that the "Review Board" text was more correct. (This manifested

even better for RBCommons.)
Tested on a page with a black header bar for the theme, and white text.

Saw the hamburger menu.