fix tried logging to non-existant channel exception

closes #6168
missing tab
tab to space
remove double click sound when switching production tabs

closes #5863
unhardcode and self-document more resource/smudge parameters
document engine limitations
bring back click sound for TAB and PageUp/Down
Add missing INotifyRemovedFromWorld impl to GlobalUpgradable
Merge pull request #6340 from cjshmyr/fix6214

Add missing INotifyRemovedFromWorld impl to GlobalUpgradable
Merge pull request #6320 from Mailaender/smudge-offset

Unhardcoded and self-documented more resource/smudge parameters
Merge pull request #6318 from Mailaender/log-session-deserialize-exception

Fixed Session.Deserialize exceptions not throwing properly
Merge pull request #6321 from Mailaender/less-nervous-clicksounds

Fixed double click sound on Tiberian Dawn production tabs
Disconnected clients now listed as '(Gone)'.