Adding CURLN* classes to MBS Xojo Plugins

As you may know we have already two CURL variants. First, the one to use your custom CURL library or the system provided one on Mac or Linux. Second, the CURLS* classes using a statically linked curl library with OpenSSL and SSH2 libraries. Now we a third option with CURLN* classes. Those use a built-in CURL library with the native SSL on Mac and Windows.
Here is a table with the built-in libraries:

Platform	CURL	CURLS	CURLN
Mac 64-bit	-	OpenSSL	DarwinSSL
Mac 32-bit	-	OpenSSL	DarwinSSL
Mac 32-bit PPC	-	OpenSSL	-
Windows 32-bit	-	OpenSSL	WinSSL
Windows 64-bit	-	OpenSSL	WinSSL
Linux 32-bit	-	OpenSSL	-
Linux 64-bit	-	OpenSSL	-
Linux 32-bit ARM	-	OpenSSL	-

For all variants you can always optionally load system or custom libraries. It's just about what is included in the plugin as default option.

Native SSL on Mac requires OS X 10.8 or newer.

If no library was loaded and you run the CURL class constructor, we will try to load the system library. That works fine on Linux and Mac.

So now it's your decision what you want to use:
The default for examples will stay with CURLSMBS as the built-in libraries provide cross platform the same experience. If you need to do native SSL, you may want to try CURLNMBS and if you plan to use your own custom CURL libraries, you can use CURLMBS. The biggest plugin in space...