Add "software collections" to kit scanning on Linux

[pwboettcher]

RedHat and CentOS systems use "software collections" to make new compilers available:

https://www.softwarecollections.org/en/scls/rhscl/devtoolset-8/

These compilers live in predictable locations, and cmake-tools kit scanning should check these locations for kit choices, perhaps even labelled "devtoolset-8", etc.

[andreeis]

Thank you for the feature request. We may not be able to implement it right away, but we will track the community reactions to evaluate where this would fit in our backlog.

[xgdgsc]

Or could you point to the code that configures common scan paths?

[nicola-lunghi]

+1 here!!!