[Maria-developers] MDEV-7781 Allow {un, }install plugins during bootstrap/skip-grant-tables

For review: https://github.com/MariaDB/server/pull/29 Simple one, this allows plugins to be removed/installed during bootstrap (opt_noacl=true) but still enforces access control in normal operation. -- -- Daniel Black, Engineer @ Open Query (http://openquery.com.au) Remote expertise & maintenance for MySQL/MariaDB server environments.