Merge pull request #900 from kcharwood/ssl_pin_example

Fix SSL Pinning
Merged upstream/master back to resolve conflicts
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 branch 'master' into invalid-ssl
Merge pull request #902 from OliverLetterer/master

Some minor stuff
Fixed if/else logic
Merge branch 'master' into invalid-ssl
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
- fix for unescaped brackets in params values
Added runtime check to disable pinning in the example

Signed-off-by: Mattt Thompson <m@mattt.me>
Replace NSData by NSUInteger in connection:didReceiveData:

Signed-off-by: Mattt Thompson <m@mattt.me>
Merge branch 'invalid-ssl' of git://github.com/kcharwood/AFNetworking into kcharwood-invalid-ssl
Minor refactoring / renaming / copy edits
Renaming allowInvalidSSLCertificate -> allowsInvalidSSLCertificate
Minor reformatting
Fixing error in documentation about defaultSSLPinningMode

Minor copy editing in documentation