build: don't install in-tree config file
config: not fatal if KVS has no config.*

Since we allow 'flux start' to run without a config file,
the KVS config.* space can be empty.  We were treating that
as a fatal error which it shouldn't be.
Merge pull request #69 from garlick/rpm-build-fixes

regressions that were preventing an RPM from being built