Add MIT license and configurable greeter palette

colors.ini.example

@@ -0,0 +1,14 @@
+[colors]
+background = #151515
+panel = #181818
+surface = #202020
+hover = #282828
+border = #2F2F2F
+focus = #454545
+text = #D0D0D0
+muted = #757575
+dim = #505050
+emphasis = #F5F5F5
+accent = #6C99BB
+accent_secondary = #547C99
+warning = #D3A04D