New CMake projects: cmake_minimum_required() must come before project()

CMake recomments to "Call the cmake_minimum_required() command at the beginning of the top-level CMakeLists.txt file even before calling the project() command. It is important to establish version and policy settings before invoking other commands whose behavior they may affect." (https://cmake.org/cmake/help/v3.6/command/cmake_minimum_required.html)

CMake projects created in Qt Creator start with project() command. This must be correct to call project() after cmake_minimum_required().

In addition, the minimum version should be bumped to 3.0, given that this version is required by Creator.