Merge branch 'release/0.4.1' into develop
prepared development iteration of next version
generate client code inside IDL directory
update patch for idl chagne (add clear method)
add test of clear for classifier
add test of clear for stat
add test of clear for regression
add jubatus.baseport argument to release:prepare
add get_client
add get_client test
bump version
Merge branch 'release/0.4.2'