Change prop=flowinfo prefix to "fli"

Anomie would like to use "fi" for a prop=fileinfo in core.
Since this module doesn't have any parameters, this isn't
a breaking change as the prefix is currently unused.

Change-Id: Ib0d27eb049d63157ff294f4d5458d022e40d85b9
Merge "Change prop=flowinfo prefix to "fli""