The message() command requires uppercase log levels. Even
though the cmake --loglevel option is not case sensitive, show
the supported values as uppercase to match the message()
docs as closely as possible, since they are related to the same
feature.

Also fixes the wrong string being shown for the warning level
by cmake --help.

It isn't yet clear whether we want to make this part of the
documented API for the install script. Remove it from the
docs before it appears in an official release for now.

Relates: #18997

Fixes: #19339

The `make_directory` command can make multiple directories in a single
invocation.  Make `remove_directory` mirror that behavior.

Fixes #18657

Fixes #19059

Relates: #18943
Co-Authored-By: Craig Scott <craig.scott@crascit.com>

Fixes: #19023

Fixes: #13204

Fixes: #16136

While we already support `VERBOSE` environment variable and
`CMAKE_VERBOSE_MAKEFILE` cached variable, add `-v` and `--verbose`
command line options to be able to activate verbose output directly from
CMake's build tool mode command line.

Also make `msbuild` honor the verbosity setting. `xcodebuild` still
doesn't honor the verbosity setting as it will need a policy added
and reworking of cmGlobalGenerator and cmsys to support
multiple command invocation.

Fixes: #13007

Extend the description section to cover all capabilities that
the "cmake" tool has.  Extend the buildsystem generation section
to introduce important concepts and describe the basic workflow.
Inspired-by: Joachim Wuttke (l) <j.wuttke@fz-juelich.de>

Extend the Synposis, and provide links to manual sections.
Add sections for `cmake --open` and `cmake --help-*`.

Introduce a new section for buildsystem generation to distinguish it
from the other functionality.  Populate it with minimal placeholder text
for now.  It will be extended later.

Co-Author: Brad King <brad.king@kitware.com>

Print the name of the **cmake** executable in boldface, so that it does
not appear less prominent than other shell commands (which are underlaid
with links).  Similarly the other tool manuals.

The allows `-E create_symlink` to work on Windows.  It utilizes
`uv_fs_symlink`.  I am still unsure exactly which Windows platforms will
work without requiring Administrator privileges or needing a user/group
with the "Create Symbolic Links" User Rights.  It does work with my
Windows 10 Pro with Developer Mode turned on.  In the test suite check
that the symlink either worked or failed with a permissions error.

Use recent changes in cmSystemTools::FileExists to check that a symlink
is broken.

Document the previously internal option of '-B' and provide a
matching source directory option with '-S'. Both '-B', and '-S'
can be used independently of each other.

While we already support `cmake --build . -- -j`, the options after `--`
are specific to the native build tool.  Add new options `--parallel
[<N>]` and `-j [<N>]` to abstract this and map to the proper option
for the native build tool.

Use `{}` to surround required parts instead of `()`.

Fixes: #17917

- add hyperlink to CMakeGraphVizOptions.cmake in cmake(1)
- improve markup in CMakeGraphVizOptions.cmake

Issue: #16791

Closes: #16784

Add `cmake -E capabilities` to report on generators, cmake version and
possibly other static capabilities of cmake.

Closes: #15462

Even in relatively small projects using `--trace` (and `--trace-expand`)
may produce a lot of output.  When developing a custom module usually
one is interested in output of only a few particular modules.

Add a `--trace-source=<file>` option to enable tracing only a subset of
source files.  The final output would be only from requested modules,
ignoring anything else not matched to given filename(s).

The `--build` mode was confusingly documented among other options,
falsely implying that it can be used anywhere on the command line.
Move the documentation to a dedicated section and clarify its usage
as s separate command line mode.