Draft: v1.6.0

• Add tests for #533
• add modlog entry to changeboardsettings just like changeglobalsettings
• Review @l29utp0's browser theme and background fixes
• 2fa enforcement
  • delete board
  • change settings
  • delete account (self or global manage)
  • add+update tests
• Update tests in general
• Update CHANGELOG, etc
• update festrings.json

dump of potential new required festrings (so far)

    "Filter mode must be a number from 0-3"
    "Replace text cannot exceed 500 characters"
    "Invalid 2FA code"
    "Invalid 2FA Code"
    "No permission"
    "Your post was blocked by a word filter"
    "global word filter auto ban"
    "global filter hit: "%s""
    "Updated settings."
    "Created board /%s/"
    "Bad request"
    "After applying filters, ${field} exceeds maximum length of %s"
    "Force Account 2FA"
    "Force Action 2FA"
    "Global"
    "PPD"
    "Users"
    "Posts"
    "Latest Activity"
    "Replace"
    "Links"
    "2FA Code"
    "Board URI"

• update locale files, with priority for new festrings