Fix cmake version bug

Author: biaks

CMakeLists.txt

@@ -1,6 +1,6 @@
 
 project(prometheus-cpp-lite)
-cmake_minimum_required(VERSION 2.6)
+cmake_minimum_required(VERSION 3.2)
 
 option(PROMETHEUS_BUILD_EXAMPLES "Build with examples" OFF)
 

core/CMakeLists.txt

@@ -1,6 +1,6 @@
 
 project(prometheus-cpp-lite-core)
-cmake_minimum_required(VERSION 2.6)
+cmake_minimum_required(VERSION 3.2)
 
 file(GLOB_RECURSE PROMETHEUS_CPP_LITE_HEADERS *.h)
 

simpleapi/CMakeLists.txt

@@ -1,8 +1,8 @@
 
 project(prometheus-cpp-simpleapi)
-cmake_minimum_required(VERSION 2.6)
+cmake_minimum_required(VERSION 3.2)
 
 add_library               (${PROJECT_NAME} STATIC "./src/simpleapi.cpp" )
 target_sources            (${PROJECT_NAME} PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include/prometheus/simpleapi.h")
 target_include_directories(${PROJECT_NAME} PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include")
-target_link_libraries     (${PROJECT_NAME} PUBLIC prometheus-cpp-lite-core)
+target_link_libraries     (${PROJECT_NAME} INTERFACE prometheus-cpp-lite-core)