Replace DSLs with JSON

[Ben Stern]

mwmg and recollect should use JSON for their configuration files instead of the ancient DSL which predates JSON.

In principle, this could allow coordinating colors with post-processing tools and network description tools.

json-c is a good library to use for this, since it's being used by svcreqollect anyway.

[Ben Stern]

Note that there are a few different versions of json-c in use and the API is still unstable, so functions that svcreqollect implements might need to be moved to a shared .o or library, and functions that it doesn't call might not be present on all systems in use.

That said, a working implementation, even if it calls functions that need to be re-abstracted or shimmed, is better than no implementation.