Please make YAML a build option

[joakim-tjernlund]

YAML pulls in new libs which takes space and existing project has no use for YAML

[sbabic]

This is of course possible, I will integrate the patch if someone posts on the ML, but some new features (namespaces, writelist) won't be available due to poorness of the original configuration file.

[LeSpocky]

Seen this with commit 0052cdc11ab826192fa08779266073ee132f3940.

[joakim-tjernlund]

Seen this with commit 0052cdc.

Thank you!