Revert "Calling cmake_minimum_required() resets the policy stack"

This reverts commit 8828bfca1747ac73b14d3c576cdb595359ddc172.
Help: Format cmake_policy command documentation

Add reStructuredText markup manually to improve formatting of the
documentation.  Organize the documentation into subsections.
Help: Reference cmake_minimum_required from cmake_policy docs

Note in a few places of the cmake_policy() command documentation
that the cmake_minimum_required() command can set policies too.

Inspired-by: Peter Kümmel <syntheticpp@gmx.net>
Merge topic 'policy-doc-updates' into next

de60a38c Help: Reference cmake_minimum_required from cmake_policy docs
51bdce12 Help: Format cmake_policy command documentation
0815f518 Revert "Calling cmake_minimum_required() resets the policy stack"
Help: Add missing space in policy CMP0020 description
Help: Format cmake_policy command documentation

Add reStructuredText markup manually to improve formatting of the
documentation.  Organize the documentation into subsections.
Help: Reference cmake_minimum_required from cmake_policy docs

Note in a few places of the cmake_policy() command documentation
that the cmake_minimum_required() command can set policies too.

Inspired-by: Peter Kümmel <syntheticpp@gmx.net>
Merge topic 'policy-doc-updates' into next

b1f4e620 Help: Reference cmake_minimum_required from cmake_policy docs
69a23cb2 Help: Format cmake_policy command documentation
0c4835a3 Help: Add missing space in policy CMP0020 description