Record more policies on targets when created

Policies CMP0027, CMP0038, and CMP0046 have per-target meaning so
record the policy settings on targets as they are created.
Tests: Simplify and document policy scopes in RunCMake.CMP* tests

Drop unnecessary NO_POLICY_SCOPE options.  Document why the remaining
options are necessary.
libarchive: Fix compliation with Open Watcom
Merge topic 'watcom-compile-libarchive' into next

52285a99 libarchive: Fix compliation with Open Watcom
Merge topic 'fix-policy-scopes' into next

50fd0a33 Tests: Simplify and document policy scopes in RunCMake.CMP* tests
b1bbee3e Record more policies on targets when created