rtcds command should set umask()

rtcds should set umask to 0002 before installing.

When installing models, rtcds needs to create directories in the /opt/rtcds/// tree that have group write permissions.

These permissions are needed by the rts@.target services which run as advligorts and attempt to write in the same directories. Advligorts is a system user that cannot be used to run rtcds from the command line.

A workaround is to run

umask 0002

from the command line before installing models with rtcds. Remember to set it back!