Fix: web-related crashes

Edited:
Bot.cs - BackgroundWorkerOnDoWork(...)
Added: other exceptions + restart
Improving error messages and fixing non-restarting bug
BUGFIX (to laggingpyro's stuff): Not sure what the purpose of this was, but it appears to cause an infinite loop sometimes
Adds User Handler feedback on bot's trade request accept/decline.
Removed obsolete reference to SteamKit's EChatEntryType.Emote
Merge pull request #536 from FunkyLoveCow/RemoveObsoleteWarning

Removed obsolete reference to SteamKit's EChatEntryType.Emote
Merge pull request #528 from BlueRaja/laggingPyroFixes

Keep bot running after a crash
Merge pull request #531 from FrozenHaxor/master

Adds User Handler feedback on bot's trade request accept/decline.
Bug-fix patch for #404

Surround web call with a try...catch. The exception is silently ignored but needs to be logged.

ref #394
Merge pull request #539 from cwhelchel/fix/i404

Bug-fix patch for #404