Signup abuse detection and blocking 1.16.7

• Change "Login Flood Limit" option to default disabled (does not change existing installs)
• Do a multi-account check even if the user login is rate limited
• Ensure tracking cookie is set on logout if it has not been set, and add some additional sanity checks around the cookie being set

• Move user notifications of detected multiple accounts outside of transaction
• Prevent unique constraint violations when processing a multiple account report which hasn't been linked to a multiple account detection event

• Avoid linking to multiple account in user registeration log lists to avoid <a> in <a> tags which breaks the layout

• Fix incorrect function name which breaks registration

• Fix possible errors when using the IP checking function for multiple accounts
• Fix "Undefined index: name" error
• Cleanup user registration logs on user delete & ensure user registration logs are assigned to the correct user on merge

• Fix errors during installing via the GUI instead of CLI
• Update XF2.1 Approval queue support, remove useless warning icon on user signup record display
• When displaying username registration log, make detected multiple-account name clickable link

• Fix possible "[E_NOTICE] Undefined index: user_id" when upgrading from old XF1 versions of Alter Ego Detector for XF1

• Display improved spam-log formatting for users in approval queue with XF2.1+

• Fix "[TypeError] Argument 1 passed to XF\Entity\User::canStartConversationWith()" with deleted user

• Properly migrate XF1 alterego report format into a XF2.1 compatible structure
  • Required if upgrading to XF2.1 reports; Error doing JSON conversion xf_report.content_info (report_id=24745): Malformed UTF-8 characters, possibly incorrectly encoded