Add a advanced example

It uses its own API which I packed between MTApi5 and MatLab.
Possible that this is useless, but errors from the .NET assembly are more tradable.

Examples/MatLab/AdvancedExample/Slack/private/http_createHeader.m

@@ -0,0 +1,11 @@
+function header = http_createHeader(name,value)
+%http_createHeader Simple function for creating input header to urlread2
+%
+%   header = http_createHeader(name,value)
+%
+%   CODE: header = struct('name',name,'value',value);
+%
+%   See Also: 
+%       urlread2
+
+header = struct('name',name,'value',value);