Merge pull request #2365 from Jmainguy/mysql_docfix

Update documentation to reflect need for mysql client

database/mysql/mysql_db.py

@@ -85,6 +85,9 @@ notes:
    - Requires the MySQLdb Python package on the remote host. For Ubuntu, this
      is as easy as apt-get install python-mysqldb. (See M(apt).) For CentOS/Fedora, this
      is as easy as yum install MySQL-python. (See M(yum).)
+   - Requires the mysql command line client. For Centos/Fedora, this is as easy as
+     yum install mariadb (See M(yum).). For Debian/Ubuntu this is as easy as
+     apt-get install mariadb-client. (See M(apt).)
    - Both I(login_password) and I(login_user) are required when you are
      passing credentials. If none are present, the module will attempt to read
      the credentials from C(~/.my.cnf), and finally fall back to using the MySQL