Overriding packages in underlay

[StefanFabian]

When overriding packages from the underlay (usually /opt/ros/), it should be made certain that these packages are built and in the path before building the remaining packages if any of them depend on them.

Normally, they would be built but since they are not available until you resource and thereby add them to the path variables, they would not be used on the first build.

TODOs

• Check if built packages and dependencies in workspace are overriding any of the packages available in an underlay
• Ensure these packages are built and available in the path before building the other packages