#150 Sidekick: provide sorting support

[daniel hahler]

It would be nice, if Sidekick would allow to sort the list, e.g. by name of nodes.

Using the CTagsSidekick plugin ("ctags" in the Sidekick dropdown), you can sort the entries, but when using PHPParser, the nodes are not sorted.

I think Sidekick should provide an interface for this, and Sidekick plugins might hook into this. But, when sidekick plugins do not provide specific sorting capabilities, Sidekick should provide a "By name" sorting at least.