Upgrade UBB.threads from a previous version

Version checks:
• Database structure version: 7.7.5
• Script version from database: 7.7.5
• Script version from filesystem: 7.7.5

Continuing will perform the following tasks:
• Upgrade your current version of UBB.threads to UBB.threads 7.7.5.
• Retain your current forum threads, posts, users and other information.