Fix for Xcode 7 beta 4

Lib/KeychainAccess/Keychain.swift

@@ -692,7 +692,7 @@ public class Keychain {
     #if os(iOS)
     @available(iOS, introduced=8.0)
     public class func generatePassword() -> String {
-        return SecCreateSharedWebCredentialPassword().takeUnretainedValue() as String
+        return SecCreateSharedWebCredentialPassword() as! String
     }
     #endif
     
@@ -916,7 +916,7 @@ extension Options {
                     let message = Status.UnexpectedError.description
                     return (attributes, NSError(domain: KeychainAccessErrorDomain, code: Int(Status.UnexpectedError.rawValue), userInfo: [NSLocalizedDescriptionKey: message]))
                 }
-                attributes[kSecAttrAccessControl as String] = accessControl.takeUnretainedValue()
+                attributes[kSecAttrAccessControl as String] = accessControl
             } else {
                 print("Unavailable 'Touch ID integration' on OS X versions prior to 10.10.")
             }