Media Playing Module with Buttons

- Replace clicks and scroll actions with dedicated buttons
  for media playing module
- Add media-playing-change module to display current media
  source and left-click to change
- Add media-playing-prev/next to play previous or next
  track
- Add media-playing-play-pause to display pause button
  when media is playing and play button when media is
  paused
- Update media-playing to use Zscroll to scroll through
  artist and title text when over limit
- Add some extra helper scripts

polybar/scripts/scroll-media-playing.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+zscroll \
+    --length $(xrdb -get polybar.maxlen) \
+    --delay 0.2 \
+    --scroll-padding " | " \
+    --match-command "`dirname $0`/get-media-status.sh" \
+    --match-text "Playing" "--scroll 1" \
+    --match-text "Paused" "--scroll 0" \
+    --update-check true "`dirname $0`/get-media-playing.sh" &
+
+wait