55a73e6b Use the cmJoin algorithm where possible.
8dc8d756 cmStandardIncludes: Add a join algorithm for string containers.
b5813cee cmInstallCommand: Remove unused variable.
This can be used to set the compiler features required by particular
targets. An error is issued at CMake time if the compiler does not
support the required feature. If a language dialect flag is required
by the features used, that will be added automatically.
Base the target_compile_features command on cmTargetPropCommandBase. This
gives us 'free' handling of IMPORTED, ALIAS, INTERFACE, non-compilable
and missing targets.