Light mode appearance: icons, text colors

[Artoria2e5]

We got the much-needed light mode in #476, but I would think that most people agree that something looks off about it. So what's really wrong with it?

Compare:

Icons

The icons on top look like thin skeletons in light mode. We need to provide inverted versions of the icons, so they look about as thick as they do in dark mode.

Text color

Text appears in a variety of colors in dark mode; more important text is given a brighter color, so they have higher contrast against the background. Light mode does not have this kind of color-importance correspondance:

• The MAC address and the encryption parts, which should be less important than the wifi name, currently renders as the same black color as the wifi name.
• The lat/lon display is too faint for its level of importance.

[rksh]

Pull requests are very welcome!

[rksh]

the menu icons work that way because the R.attr.colorControlNormal tint doesn't appear to get applied to them - could be because they from the android.R.drawable.ic_menu... family

[rksh]

ah, yes, they're image chains.

[rksh]

#725 submitted to slim down the lines of the new icons somewhat.