Change Project.GenerateDescriptionFile behavior

Now returns a ProjectFile instance.
Refactor InfoTabViewModel

Hopefully makes selecting a Description/Space less confusing.
delete unused description files when closing project
Dynamically Update SelectedItem's Text

Also refactor DescriptionInfoTabViewModel class
catch taskcanceledexception
Enable or disable Textbox based on var being set

The var being SelectedItem
added preprocessor commands to get rid of support for extended description

created new configuration called ZAGGA that has the zagga conditional
variable set
Merge branch 'valdev'

Conflicts:
	LiveDescribe/LiveDescribe/LiveDescribe.csproj
Merge branch 'master' of github.com:IMDC/LiveDescribe-Desktop