Cleaned up the attributes tests
Changed contentRendered property to defaul to `null` instead of `false` like the others
Attempt at getting a better render pass algorithm
Added CONTRIBUTING.md
clarified contributing guidelines
clarified contributing guidelines
Merge branch 'master' into dev
Updated readme header with logo and screencast
Merge branch 'master' into dev
v6.15.0. Improvement.

- v6.15.0 December 3, 2012
	- [Nodejitsu](http://nodejitsu.com/) Support
Merge branch 'master' into dev-render
renderPasses configuration option now going
v6.16.0. Improvement.

- v6.16.0 December 4, 2012
	- The amount of render passes is now customisable via the
`renderPasses` configuration option, defaults to `1`
		- Increment this value dependening on how many levels of
cross-document references you have (e.g. 2 passes for C includes B, B
includes A)
	- The render pass functionality has been changed to render all
documents that don't reference anything else first, then for each
additional render pass, render documents that do reference others
		- Previously it would render both types of documents in the one
batch, which resulted in hit and miss results
		- Doing this, we now safely have the default `renderPasses` value set
to `1` which has the same effect as the traditional `2` render pass
		- Refer to [issue #359](https://github.com/bevry/docpad/issues/359)
for more information
Cleaned up the Meta Data handling

- Removed useless `Document::initialize` and `Document::getMeta`
- Updated `File::getMeta` to create meta if it doesn't exist yet
- Added `Base::setDefaults`, `File::setMeta`, and
`File::setMetaDefaults`
v6.17.0. Clean.

- v6.17.0 December 4, 2012
	- Updated
		- `File::getMeta` to create meta if it doesn't exist yet
	- Removed
		-  `Document::initialize` didn't do anything
		-  `Document::getMeta` didn't do anything
		-  `File::readFile` merged into `File::parse`
		- `File::parseData` renamed to `File::parse` and cleaned signficantly
	- Added
		- `Base::setDefaults` to update attributes that haven't been set
		- `File::setMeta` to update the meta more easily than
`File.getMeta().set`
		- `File::setMetaDefaults` to update the meta attributes that haven't
been set
		- `File::getContent` to get the content or buffer
		- `File::getOutContent` to get the rendered content, or content, or
buffer
		- `File::getStat` to get the stat
		- `File::setBuffer` to set the buffer
		- `File::getBuffer` to get the buffer
v6.17.1. Improvement.

- v6.17.1 December 4, 2012
	- Updated misc internals to use the new `File::getOutContent` call
v6.17.2. Bugfix.

- v6.17.2 December 5, 2012
	- `watch` and `server` actions now perform an initial generation
		- Thanks [Khalid Jebbari](https://github.com/DjebbZ), [Vladislav
Botvin](https://github.com/darrrk)
		- Closes [#369](https://github.com/bevry/docpad/issues/369),
[#368](https://github.com/bevry/docpad/issues/368),
[#366](https://github.com/bevry/docpad/issues/366)
Fixed loading issue of files
Merge pull request #371 from darrrk/master

Fixed loading of files ref #370
v6.17.3. Bugfix.

- v6.17.3 December 5, 2012
	- Fixed an issue introduced in v6.17.0 that prevented files from
reloading under certain circumstances
		- Thanks [Vladislav Botvin](https://github.com/darrrk) for [issue
#370](https://github.com/bevry/docpad/issues/370) and [pull request
#371](https://github.com/bevry/docpad/pull/371)