Smaller UI Bugfixes

[Groruk]

Description

Some small fixes for the upcoming SourceBans++ 1.7.0 release.

Changes:

• Fix hostname display error on "Report a Player / Submit a Ban" page (Fix Server list bug in submit a ban #509)
• Fix tab switching (Fix i cannot ban player on Ban Submissions #587)
• Cleanup SetupBan() function
• Return false on empty SteamID conversion
• Add "No Steam Community ID present" message to UI
• Make IP search links from the "home" page only available to admins (Fix Security: IP Displays to users not logged in #599)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.