Core Templating code

[jayfresh]

This is the minimal set of code to add Templating into the core, where Templating refers to TiddlyTemplating? as described at:

http://tiddlywiki.org/wiki/TiddlyTemplating

This defines a new core file, Templating.js, which contains code for the following: * expandTemplate - a function to render an array of tiddlers with a template * templateFormatter - simple formatter for processing templates * templateTiddlers - macro to find a set of tiddlers and render them once each through a template * templateTags - macro to render a tiddler's tags through a template

This patch does not add in an actual use case of templating, but leaves that to future patches, instead preferring to bake the core mechanism into the core.

[jayfresh]

Patch for ticket #700