Pinning certificates will now trust all derived certificates.
Fixes SecTrustCreateWithCertificates expecting an array as first argument.
Merges master.
Merge pull request #882 from OliverLetterer/derived-certificates

Pinning certificates will now trust all derived certificates.
Now using errSecSuccess instead of noErr for Security frameworks OSStatus.
Now using NSParameterAssert instead of NSCParameterAssert.
Merge pull request #902 from OliverLetterer/master

Some minor stuff
Check for finished operations in order to increments the `numberOfFinishedOperations` count
Merge pull request #911 from runmad/master

Check for finished operations, not cancelled operations to increment the numberOfFinishedOperations count