jubaconv accept v.0.4 configuration: fix #223
moved directory of third-party library (fixed #235)
moved directory of third-party library (fixed #235)
some warning reduced, signed-unsigned comparison
fix not-updating min/max values (fixes #238)
add validation to config_tozk
fixed codestyle
add unittest
fixed wrong include
Merge pull request #241 from unnonouno/feature/fix-jubaconv

jubaconv accept v.0.4 configuration: fix #223
Merge pull request #245 from rimms/validate_config

Validate config format (json) before writing to ZooKeeper
remove portable_mixer.hpp from installation (fix #248)
remove unused re_convert prototype (fix #231)
build graph_base_test.cpp (fix #234)