Install plyr via npm and stage appropriately for video_player visualization

config/plugins/visualizations/video_player/package.json

@@ -0,0 +1,11 @@
+{
+    "name": "video_player",
+    "version": "1.0.0",
+    "license": "MIT",
+    "dependencies": {
+        "plyr": "^3.6.2"
+    },
+    "scripts": {
+        "build": "mkdir -p static/dist && cp node_modules/plyr/dist/plyr.js node_modules/plyr/dist/plyr.css static/dist"
+    }
+}

config/plugins/visualizations/video_player/templates/video_player.mako

@@ -7,11 +7,11 @@
 <head lang="en">
     <meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1"/>
     <title>Video player</title>
-    ${h.stylesheet_link(app_root + 'css/plyr.css')}
-    ${h.stylesheet_link(app_root + 'css/video_player.css')}
+    ${h.stylesheet_link(app_root + 'dist/plyr.css')}
+    ${h.stylesheet_link(app_root + 'video_player.css')}
 </head>
 <body class="body-video-player">
-    ${h.javascript_link( app_root + "js/plyr.js")}
+    ${h.javascript_link( app_root + "dist/plyr.js")}
     <video id="video-container" playsinline controls>
         <source src="${h.url_for( controller='/datasets', action='index')}/${hda.id}/display" type='video/mp4' />
         <source src="${h.url_for( controller='/datasets', action='index')}/${hda.id}/display" type='video/mkv' />