Do not vendor cookbooks using Berkshelf anymore

Instead, use the Berkshelf support in knife-solo and the
vagrant-berkshelf plugin on Vagrant

cookbooks/mysql/templates/default/systemd/mysqld.service.erb

@@ -1,16 +0,0 @@
-[Unit]
-Description=mysql_service[mysql-<%= @config.instance %>]
-After=syslog.target
-After=network.target
-
-[Service]
-Type=simple
-User=<%= @config.run_user %>
-Group=<%= @config.run_group %>
-ExecStart=<%= @mysqld_bin %> --defaults-file=<%= @etc_dir %>/my.cnf --basedir=<%= @base_dir %>
-ExecStartPost=/usr/libexec/mysql-<%= @config.instance %>-wait-ready $MAINPID
-TimeoutSec=300
-PrivateTmp=true
-
-[Install]
-WantedBy=multi-user.target