SSL Support

This provides SSL support to quickfix and thereby implements issue  https://github.com/connamara/quickfixn/issues/18

The names of the different settings are similar to those suggested in the issue thread and are all documented, both in code and in tutorial\configuration

The fastest approach to get the examples running using SSL is to first install the following three certificates (double click on them in windows and follow the guide) into the personal store and then specifying the "\_ssl" (eg tradeclient\_ssl.cfg instead of tradeclient.cfg) variant of the configuration file for the exampel project

* Examples\QuickFixn-TestCA.pfx
* Examples\QuickFixn-TestServer.pfx
* Examples\QuickFixn-TestClient.pfx

My original ide was to specify filepath and password to the certificates in the example projects, but it did not seem 100% reliable when using .net 3.5 (It worked and then stopped working after cloning my reposit to a new directory so it may be to long filenamse or maybe I just needed a computer restart). 
Having the certificates installed on the computer is better from a security point of view since you don't have to store the password in plain text in the configuration file, so I think we should use this approach anyway as we would otherwise maybe fool people into using it in production otherwise.

**Note**: Don't install the QuickFixn-TestCA.pfx as a trusted root CA unless you know what you are doing. (Anybody who have downloaded it from guithub could create a certificate for *.google.com, your bank or any other webbpage and you would trust it)