Set explicit flag to use Boost MULTITHREADED (#182)

* Set explicit flag to use Boost MULTITHREADED

* Bump CMake version

Author: awegrzyn

CMakeLists.txt

@@ -6,6 +6,7 @@ CMAKE_MINIMUM_REQUIRED(VERSION 3.5.2 FATAL_ERROR)
 set(Boost_USE_STATIC_RUNTIME OFF)
 set(Boost_USE_STATIC_LIBS OFF)
 set(BUILD_SHARED_LIBS ON)
+set(Boost_USE_MULTITHREADED ON)
 
 # Set cmake policy by version: https://cmake.org/cmake/help/latest/manual/cmake-policies.7.html
 if(${CMAKE_VERSION} VERSION_LESS 3.12)
@@ -16,7 +17,7 @@ endif()
 
 # Define project
 project(Monitoring
-  VERSION 2.4.0
+  VERSION 2.6.6
   DESCRIPTION "O2 Monitoring library"
   LANGUAGES CXX
 )