Unify config syntax in default files

- Include a link to the relevant KB article for more info
- Use spaced around the equal sign for better readability and so that
  the examples are more aligned with the general style in the KB
- Load plugins with just the base name, the .so is optional and excess

debian/additions/mariadb.cnf

@@ -12,6 +12,8 @@
 # One can use all long options that the program supports.
 # Run program with --help to get a list of available options and with
 # --print-defaults to see which it would actually understand and use.
+#
+# If you are new to MariaDB, check out https://mariadb.com/kb/en/basic-mariadb-articles/
 
 #
 # This group is read both by the client and the server

debian/additions/mariadb.conf.d/50-client.cnf

@@ -5,11 +5,11 @@
 
 [client]
 # Example of client certificate usage
-# ssl-cert=/etc/mysql/client-cert.pem
-# ssl-key=/etc/mysql/client-key.pem
+# ssl-cert = /etc/mysql/client-cert.pem
+# ssl-key = /etc/mysql/client-key.pem
 #
 # Allow only TLS encrypted connections
-# ssl-verify-server-cert=on
+# ssl-verify-server-cert = on
 
 # This group is *never* read by mysql client library, though this
 # /etc/mysql/mariadb.cnf.d/client.cnf file is not read by Oracle MySQL

debian/additions/mariadb.conf.d/50-mysqld_safe.cnf

@@ -9,12 +9,12 @@
 # with the following contents:
 #
 # [Service]
-# User=mysql
-# StandardOutput=syslog
-# StandardError=syslog
-# SyslogFacility=daemon
-# SyslogLevel=err
-# SyslogIdentifier=mysqld
+# User = mysql
+# StandardOutput = syslog
+# StandardError = syslog
+# SyslogFacility = daemon
+# SyslogLevel = err
+# SyslogIdentifier = mysqld
 #
 # For more information, please read https://mariadb.com/kb/en/mariadb/systemd/
 
@@ -23,6 +23,6 @@
 # It has been reported that passwords should be enclosed with ticks/quotes
 # especially if they contain "#" chars...
 
-nice   = 0
+nice = 0
 skip_log_error
 syslog

debian/additions/mariadb.conf.d/60-galera.cnf

@@ -2,19 +2,20 @@
 # * Galera-related settings
 #
 # See the examples of server wsrep.cnf files in /usr/share/mysql
+# and read more at https://mariadb.com/kb/en/galera-cluster/
 
 [galera]
 # Mandatory settings
-#wsrep_on=ON
-#wsrep_provider=
-#wsrep_cluster_address=
-#binlog_format=row
-#default_storage_engine=InnoDB
-#innodb_autoinc_lock_mode=2
+#wsrep_on = ON
+#wsrep_provider =
+#wsrep_cluster_address =
+#binlog_format = row
+#default_storage_engine = InnoDB
+#innodb_autoinc_lock_mode = 2
 
 # Allow server to accept connections on all interfaces.
-#bind-address=0.0.0.0
+#bind-address = 0.0.0.0
 
 # Optional settings
-#wsrep_slave_threads=1
-#innodb_flush_log_at_trx_commit=0
+#wsrep_slave_threads = 1
+#innodb_flush_log_at_trx_commit = 0

storage/spider/spider.cnf

 [mariadb]
 #
-#  uncomment the following line to enable SPIDER storage engine
+# Uncomment line to enable
 #
-#plugin-load-add=ha_spider.so
+#plugin-load-add = ha_spider
+
+# Read more at https://mariadb.com/kb/en/spider/