Removed unused files
Removed useless #import directives as UIKit is not required
Converted NSData+JiveBase64.m to ARC

Also used -[NSString initWithBytesNoCopy:length:encoding:freeWhenDone:]
Imported required headers in Jive.m

Assuming a header will be included by the PCH is the best way to prevent others from compiling your code
Added OSX compatibility