databases/mariadb55-server: Fix vulnerabilities

• Add vulnerability patch from upstream
• Improve OQGraph BROKEN message
• Take maintaintership

MFH: 2017Q1
Security: 7c27192f-0bc3-11e7-9940-b499baebfeaf
Security: 4d2f9d09-ddb7-11e6-a9a5-b499baebfeaf
Security: CVE-2017-3313
Security: CVE-2017-3302