Update: OpenIGTLink

Signed-off-by: ayamada <ayamada0614@yahoo.co.jp>
Merge branch 'master' of https://github.com/SNRLab/SlicerROSIntegrationTraining
Update: Remove .DS_Store for issue #17

Signed-off-by: ayamada0614 <ayamada0614@yahoo.co.jp>