Add arrow icons for episode navigation

public_html/images/icons/arrow-previous-plain.svg

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   viewBox="0 0 6.3102736 9.6969385"
+   version="1.1"
+   id="svg1106"
+   width="6.3102736"
+   height="9.6969385"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg">
+  <defs
+     id="defs1103" />
+  <g
+     id="layer1"
+     transform="translate(-92.71506,-46.084171)">
+    <path
+       id="path9831"
+       style="color:#000000;fill:#000000;fill-opacity:0.984314;stroke:#000000;stroke-width:0.463;stroke-linecap:round;stroke-linejoin:round;stroke-miterlimit:4;stroke-dasharray:none;stroke-opacity:1"
+       d="m 97.584696,55.549619 1.209147,-1.2065 -3.421063,-3.423708 3.386663,-3.386667 -1.21708,-1.217083 -4.595813,4.595813 z" />
+  </g>
+</svg>