New Tiddlywiki functionality fro TiddlyDesktop

[Matthew Lauber]

All,

   I've put up a PR for creating new wikis from within TiddlyDesktop.  It allows you to  select a template from a drop down and then copy that template to a new file which is added to your list and opened for editing.  The drop down can be configured via the settings window.  Take a look at the PR for a quick look at the UI.  

https://github.com/Jermolene/TiddlyDesktop/pull/90