Ability to configure front matter values

[paulrobertlloyd]

Possible alternative to #17…

I would like to override the default front matter values, but there is currently no way to override these that I can see. For example, I don’t need to set layout: micropubpost, as I have front matter defaults set to configure my layouts. Might it be possible to set front matter defaults in a config value?

(I also don't need to set slug and title, FYI)

[voxpelli]

I agree, this should be made configurable. If you're up for a PR, then it would be for https://github.com/voxpelli/node-format-microformat, otherwise I'll get to this eventually (not had the most of time for stuff like this the last weeks unfortunately)