better role-app filtering, with platform info and wildcard checks, fixes #167.
catch and handle exception when all apps do not start.
Merge pull request #168 from robotics-in-concert/start_app_engines

Catch and handle exception when all apps do not start.
Merge branch 'hydro-devel' of https://github.com/robotics-in-concert/rocon_concert into hydro-devel
remove unused variable.
Merge branch 'hydro-devel' into scheduler