Added reactive loading. Fixes #734. Discussion at #736. Needs documentation.
Merge branch 'master' into reactiveloading
Fixed merge 308c3003d00545abb7bf3a2b44ffcf34668385a1 of 1ff5f4ab910fd836616780c971fc5d39d0af7f65
Moved the missing layout error check from contextualize step to render step, as the layout may not be there if we are still loading documents
v6.58.0. Improvement.

- v6.58.0 December 16, 2013
	- Deprecated and removed the `parseBefore` and `parseAfter` events
		- Files are now parsed as they are loaded in, rather than only when
they reach the generation cycle
		- See [issue #736](https://github.com/bevry/docpad/issues/736) for
discussion and upgrade options
	- Dynamic documents now have access to templateData that plugins have
extended (regression since always)
		- Dynamic documents now go through the standard generation process
		- Thanks to [Steve McArthur](https://github.com/SteveMcArthur),
[Marcus Stong](https://github.com/stongo) for
[docpad/docpad-plugin-feedr#5](https://github.com/docpad/docpad-plugin-f
eedr/issues/5)
	- Documents that want to be rendered, but not written, are now
rendered (possible regression since v6.55.0)
		- Thanks to [pflannery](https://github.com/pflannery) for [issue
#734](https://github.com/bevry/docpad/issues/734)
	- Moved the missing layout error check from contextualize step to
render step, as the layout may not be there if we are still loading
documents