Build system: Removed hard requirement on BOOST_ROOT being set as environment variable, it can now be also passed as command line argument to cmake and fix compile warning with boost 1.73

dep/boost/CMakeLists.txt

@@ -9,7 +9,7 @@
 # implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 
 if(WIN32)
- set(BOOST_DEBUG ON)
+  set(BOOST_DEBUG ON)
   if(DEFINED ENV{BOOST_ROOT})
     set(BOOST_ROOT $ENV{BOOST_ROOT})
     if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 19.0)
@@ -21,7 +21,7 @@ if(WIN32)
         ${BOOST_ROOT}/lib${PLATFORM}-msvc-14.1
         ${BOOST_ROOT}/lib${PLATFORM}-msvc-14.0)
     endif()
-  else()
+  elseif(NOT DEFINED Boost_DIR AND NOT DEFINED BOOST_ROOT AND NOT DEFINED BOOSTROOT)
     message(FATAL_ERROR "No BOOST_ROOT environment variable could be found! Please make sure it is set and the points to your Boost installation.")
   endif()
 
@@ -84,7 +84,8 @@ target_compile_definitions(boost
     -DBOOST_OPTIONAL_USE_OLD_DEFINITION_OF_NONE
     -DBOOST_SERIALIZATION_NO_LIB
     -DBOOST_CONFIG_SUPPRESS_OUTDATED_MESSAGE
-    -DBOOST_ASIO_NO_DEPRECATED)
+    -DBOOST_ASIO_NO_DEPRECATED
+    -DBOOST_BIND_NO_PLACEHOLDERS)
 
 if (NOT boost_filesystem_copy_links_without_NO_SCOPED_ENUM)
   target_compile_definitions(boost