Help: Add option to create and install Qt .qch file.
Policies: omit warnings about unset policies when they are actually set to NEW
Merge topic 'generate-qch-doc' into next

a0b7ab01 Help: Add option to create and install Qt .qch file.
Merge topic 'fix_policy_diagnostics' into next

77b581c2 Policies: omit warnings about unset policies when they are actually set to NEW