Several improvements including the possibility to skip arbitrary dependencies from CK workflows

• fixed copyright note in the License file
• improved problem reporting in module:program
• important fix in "module:program" detected while preparing MLPerf inference out-of-the-box benchmarking: clean tmp directory when running CK workflow that doesn't have compilation!
• added --remove_deps flag to module:program and module:env as suggested by CK users to be able to remove some dependencies from CK program workflows and thus use natively installed compilers, tools, libraries and other components - useful to debugging and testing. This flag takes a list of keys from dependencies from a given program workflows separated by comma.
• added the latest contributors to the CK project.