* mariadb: update "What is MariaDB?"
Update description/license plege based on https://mariadb.org/about/
Update predominate users based on more recentl wikipedia links.
Drop-in compatibility is considered by many as overstepping the mark,
despite being moderately true, so limit the statement somewhat.
* mariadb: change hosting repository
* mariadb: replace logo
From https://mariadb.org/wp-content/uploads/2019/01/mariadb_org_rgb_v.png
* mariadb: reference JIRA for issues
* mariadb: content reference mariadb command line and docs
* mariadb: reference as MariaDB logs/configuration file
* mariadb: change README-short.txt
* mariadb: update maintainer
* mariadb: add get-help.md
* mariadb: *.sql.xz files initialization allowed
* mariadb: network naming from #1860
Daniel Black
