akka/akka — pull request #15837 by drewhk (2014-09-09 13:25:39+00:00)
Title: N-way merge first attempt

**DO NOT MERGE**

*This is an early preview with commented out lines, printlns, FIXMEs, bugs and whatnot.*

N-way merge and infrastructure for more complex fan-in operations. Currently following a strictly layered materialization that does not allow cycles.