This is useful when zlib-ng is embedded into another library,
such as ITK: https://itk.org/Closes#1025.
Co-authored-by: Mika Lindqvist <postmaster@raasu.org>
Use recommended naming conventions for variables
See https://cmake.org/cmake/help/v3.0/command/project.html?highlight=project for
the common conventions.
The project() command stores the version number and its components in variables
PROJECT_VERSION, <PROJECT-NAME>_VERSION
PROJECT_VERSION_MAJOR, <PROJECT-NAME>_VERSION_MAJOR
PROJECT_VERSION_MINOR, <PROJECT-NAME>_VERSION_MINOR
PROJECT_VERSION_PATCH, <PROJECT-NAME>_VERSION_PATCH
PROJECT_VERSION_TWEAK, <PROJECT-NAME>_VERSION_TWEAK
If zlib-compat is enabled, keep libz name.
If zlib-compat is disabled, use libz-ng name.
Add new .map file for -ng mode, with prefixed function names.
This commit only containes preparatory changes to
the central parts of the build system.
