add remote process timeout
refactor remote module
refactor process module
add remove process timeout
fix problem that logs are not recorded when process failed to start
improve default envdef.py
fix test failures
add config generator (fix #17)
add get_configs
fix use case test to run with config variation
add include syntax to envdef file (fix #26)
Merge remote-tracking branch 'origin/master' into develop

Conflicts:
	lib/jubatest/constants.py
support Jubatus 0.6.0 model file name (refs #27)
support Jubatus 0.6.0 log format (refs #27)
improve envdef.py example
support timeout_sec option in get_client
take care of constructor failures in LocalSubprocess
refactor remote module
use separate process group for subprocesses to avoid signal propagation
fix timeout option not working in SyncRemoteProcess.run; add test