Add Solarized color scheme

[ngg]

This PR adds a new color scheme that looks good in Solarized terminals. It is a slight modification of the Black Night scheme. Based on https://bitbucket.org/ajenkins/htop-solarized/src/

[willvousden]

This seems to be a sensible addition. The current "Broken Gray" theme seems to be a compromise, since it doesn't make full use of the Solarized palette.

Solarized is an excellent colour scheme, but due to xterm limitations it requires applications to use a specifically designed theme. Since Solarized is so widely used, it seems to make sense to include such a theme in htop (since user-defined themes aren't supported).

[antoineco]

The end result looks like this on macOS' Terminal.app with a Solarized Dark color scheme: (bold text is displayed with bright colors, just like the GNOME Terminal)

I find the usage of cyan excessive, but at least all the text is readable.

---

In comparison, this is how the scheme renders with the following changes, in the same conditions as above:

--- a/CRT.c
+++ b/CRT.c

   [COLORSCHEME_SOLARIZED] = {
-      [RESET_COLOR] = ColorPair(Cyan,Black),
+      [RESET_COLOR] = ColorPair(White,Black),
-      [DEFAULT_COLOR] = ColorPair(Cyan,Black),
+      [DEFAULT_COLOR] = ColorPair(White,Black),

---

Since Solarized is so widely used, it seems to make sense to include such a theme in htop (since user-defined themes aren't supported). -- @willvousden

I also believe this comment is relevant, the future Convergent Terminal from Ubuntu will adopt Solarized as its default color scheme. @hishamhm wether this is a wise decision or not, it seems important that widely used tools like htop offer a certain level of compatibility with solarized.

edit: I just noticed the "Broken Gray" color scheme which looks good in Solarized terminals as well actually.

[willvousden]

Can we expect this PR to be merged?