Give better error messages from Trade.Poll(), use an enum for trade_status
On trade_status == 2, retry the request later
Correctly set _otherUserTimingOut
(I'm not sure what happened to this code, I'm 100% I wrote it...)
Renaming private fields to keep code-style consistent
Merge branch 'JessecarMaster' into TradeErrorImprovements

Conflicts:
	SteamBot/UserHandler.cs
Merge branch 'JessecarMaster' into TradeErrorImprovements

Conflicts:
	SteamTrade/Trade.cs
Merge pull request #615 from BlueRaja/TradeErrorImprovements

Better error-messages for trades