Issue #370: Fix problem where stream errors would not be detected

It seems the comparison has always been against the wrong enum, so the check would never trigger previously.

The latest llvm issues a warning like this:
ASIDataDecompressor.m:161:34: Comparison of constant 'NSStreamEventErrorOccurred' (8) with expression of type 'NSStreamStatus' (aka 'enum NSStreamStatus') is always false

[patch from github user 'OpenFibers', thanks!]
Fix an analyser warning in the latest llvm

Error is: ASIHTTPRequest.m:4571:44: Division by zero

I think this may be a false warning, or llvm is assuming that "[bandwidthUsageTracker addObject:...];" has failed for some reason, but it does no harm to double check that we're not going to divide by zero.
Updated deprecated method 

addTimeInterval changed to dateByAddingTimeInterval
Merge pull request #375 from mineschan/master

Updated deprecated method addTimeInterval
ASIInputStream Support ARC
ASIDataDecompressor ARC
ASIDataCompressor ARC
ASIHTTPRequest.h .m partial support ARC
change + (void)updateProgressIndicator:(id*)indicator withProgress:(unsigned long long)progress ofTotal:(unsigned long long)total;to + (void)updateProgressIndicator:(id)indicator withProgress:(unsigned long long)progress ofTotal:(unsigned long long)total;
Solve some ARC problem
Solve PerformSelectorLeakWarning
Modify 2 properties
change + (void)performSelector:(SEL)selector onTarget:(id *)target withObject:(id)object amount:(void *)amount callerToRetain:(id)caller; to  + (void)performSelector:(SEL)selector onTarget:(id)target withObject:(id)object amount:(void *)amount callerToRetain:(id)caller;
fix a memery leak
fix a memery leak
fix a warning
update README
ASIFormDataRequest support ARC
ASINetwrokQueue support ARC
ASIAuthenticationDialog support ARC