Update favicon and fix gem issues

_site/assets/browserconfig.xml

@@ -2,7 +2,7 @@
 <browserconfig>
     <msapplication>
         <tile>
-            <square150x150logo src="/assets/mstile-150x150.png"/>
+            <square150x150logo src="/mstile-150x150.png"/>
             <TileColor>#da532c</TileColor>
         </tile>
     </msapplication>

_site/assets/safari-pinned-tab.svg

@@ -1,15 +0,0 @@
-<?xml version="1.0" standalone="no"?>
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 20010904//EN"
- "http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd">
-<svg version="1.0" xmlns="http://www.w3.org/2000/svg"
- width="231.000000pt" height="231.000000pt" viewBox="0 0 231.000000 231.000000"
- preserveAspectRatio="xMidYMid meet">
-<metadata>
-Created by potrace 1.14, written by Peter Selinger 2001-2017
-</metadata>
-<g transform="translate(0.000000,231.000000) scale(0.100000,-0.100000)"
-fill="#000000" stroke="none">
-<path d="M0 1160 l0 -1090 1155 0 1155 0 0 1090 0 1090 -1155 0 -1155 0 0
--1090z"/>
-</g>
-</svg>

_site/assets/site.webmanifest

@@ -3,9 +3,14 @@
     "short_name": "",
     "icons": [
         {
-            "src": "/assets/android-chrome-192x192.png",
+            "src": "/android-chrome-192x192.png",
             "sizes": "192x192",
             "type": "image/png"
+        },
+        {
+            "src": "/android-chrome-512x512.png",
+            "sizes": "512x512",
+            "type": "image/png"
         }
     ],
     "theme_color": "#ffffff",