Fix color of inactive airline

Make it less cryptic on non-transparecified theme
Fix xmobar date/time script runner

As of xmobar 0.19, `Com` uses safer runInteractiveProcess instead of spawning a
shell. This patch worksaround this behavior. See:

https://github.com/jaor/xmobar/issues/127
https://github.com/jaor/xmobar/pull/120
Update submodules