Move all files installed below /usr/share in the same directory

Also move the grub theme to /usr/share/grub/themes/kali/ as installing
files in /boot/ is problematic on arm where /boot is often a vfat
partition that doesn't support hardlinks as required by dpkg.

Gbp-Dch: Full

share/themes/Kali-Dark/gtk-2.0/gtkrc

@@ -0,0 +1,21 @@
+gtk-color-scheme = "base_color: #272a34"
+gtk-color-scheme = "text_color: #ffffff"
+gtk-color-scheme = "bg_color: #23252e"
+gtk-color-scheme = "fg_color: #ffffff"
+gtk-color-scheme = "tooltip_bg_color: #4B5162"
+gtk-color-scheme = "tooltip_fg_color: #ffffff"
+gtk-color-scheme = "selected_bg_color: #2777ff"
+gtk-color-scheme = "selected_fg_color: #ffffff"
+gtk-color-scheme = "insensitive_bg_color: #292c36"
+gtk-color-scheme = "insensitive_fg_color: #8b8c90"
+gtk-color-scheme = "notebook_bg: #272a34"
+gtk-color-scheme = "dark_sidebar_bg: #353945"
+gtk-color-scheme = "link_color: #2777ff"
+gtk-color-scheme = "menu_bg: #272a34"
+
+gtk-icon-sizes = "gtk-button=15,15" # This makes button icons smaller.
+gtk-auto-mnemonics = 1
+gtk-primary-button-warps-slider = 1
+
+include "main.rc"
+include "menubar-toolbar/menubar-toolbar-dark.rc"