cmake: put cmake_minimum_required before project()

This is sternly advised by cmake, see notes in [cmake_minimum_required()][1] description.

[1]: https://cmake.org/cmake/help/latest/command/cmake_minimum_required.html
 suppresses cmake warning

Author: Fat-Zer

CMakeLists.txt

@@ -1,6 +1,6 @@
+CMAKE_MINIMUM_REQUIRED(VERSION 2.6.0)
 PROJECT(instead)
 
-CMAKE_MINIMUM_REQUIRED(VERSION 2.6.0)
 SET(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake)
 
 IF("${PROJECT_SOURCE_DIR}" STREQUAL "${PROJECT_BINARY_DIR}")