Add plyr as player default and remove NodeJS, npm and videojs

extlib/plyr/build-instructions.md

@@ -0,0 +1,23 @@
+# Build steps for Plyr (3.6.8)
+
+Tested on Hyperbola GNU with Linux-libre.
+
+First install npm (node package manager).
+
+Clone the repo to a location of your choosing:
+```
+git clone https://git.sr.ht/~heckyel/plyr
+cd plyr
+```
+
+Install Plyr's dependencies:
+```
+npm install
+```
+
+Build with npm:
+```
+npm run build
+```
+
+plyr.js and other files will be in the `dist` directory.