TemplateInformationResult adjustments

Changed TemplateInformationResult.DefaultContent and TemplateInformationResult.Sections to deserialize into a Dictionary<string,string> for easy lookup of content / sections.  The mailchimp docs do show this list of property/value pairs, although it isn't terribly clear in their docs.  This is how it is sent down to the client too in all the testing I've done against my templates.  ServiceStack appears to deserialize it correctly into the dictionary.

The .localhistory in .gitignore is from a Visual Studio plugin I use to track changes to files locally.

PS I'm new to git and its my first time contributing to github.  Let me know if I've messed something up!  :-)