Implement meeting system

[JulianusIV]

• database:
• meeting
• topic
• initiator
• meeting add
• meeting create initiator
• meeting create topic
• meeting edit initiator
• meeting edit topic
• meeting delete
• meeting delete initiator
• meeting delete topic
• meeting show
• meeting initiator show
• meeting topic show

[JulianusIV]

Closing, as it has gotten irrelevant