* Introduce `CMAKE_PROJECT_VERSION` and the corresponsing components:
`CMAKE_PROJECT_VERSION_MAJOR`, `CMAKE_PROJECT_VERSION_MINOR`,
`CMAKE_PROJECT_VERSION_PATCH` and `CMAKE_PROJECT_VERSION_TWEAK`.
* `CPack` module use `CMAKE_PROJECT_VERSION_MAJOR`,
`CMAKE_PROJECT_VERSION_MINOR` and `CMAKE_PROJECT_VERSION_PATCH`
to initialize corresponsing CPack variables.