Update Travis config to run format check

bin/html-beautify-check.sh

@@ -1,12 +1,14 @@
+#!/bin/bash
+
 # A custom script, that formats the file(s) with html-beautify,
 # but instead of changing it, it only errors with 0/1 if it needs to be changed
 # Ref: https://web.archive.org/web/20190522172323/https://medium.com/@jtomaszewski/keep-your-code-clean-forever-65c71f7f2df
-APPDIR=$(realpath $(dirname $(dirname $0)))
+APPDIR=$(readlink -f $(dirname $(dirname $0)))
 TMPDIR=$(mktemp -d)
 cd $APPDIR
 
 for line in $*; do
-  filepath=$(realpath $line)
+  filepath=$(readlink -f $line)
   file=${filepath/$APPDIR\//}
   mkdir -p $TMPDIR/$(dirname $file)
   cp $APPDIR/$file $TMPDIR/$file