isMatch = (tiddler, filter) =>
  getTiddlerRef(tiddler) === getMatches(filter, [ getTiddlerRef(tiddler) ])[0]
Tries to match a single tiddler object against a filter.
Returns a boolean value.

@param {Tiddler} tiddler - The object to apply the filter to.
@param {TiddlyWikiFilter} filter - The filter to use.
@return {boolean} True if the tiddler matches the filter, false otherwise.