Real world use cases. Allow for dots in names. Handle backspace. Run automatic mutation merging. Load multiple rdf gzips, etc.

Optimized Posting List, yes! AddMutation now largely runs in O(log M + log N), plus potential element shift for mindex. Also reduced complexity.

Handle reading rdf data from files. Use underscores for uid and xid, keeping it in sync with internal usage. Output uids as hex.

Make list matrix work, yeah! This would serialize uids for the next query, which would then again return a matrix, so on and so forth.

BREAKING change: convert to JSON. Given we're not tracking uids for each query uid, this will cause problems for the result. So, have to re-structure stuff here.