partial merge bitcoin#15382: add RunCommandParseJSON

contains only 8314c23

depends/packages/boost.mk

@@ -27,7 +27,9 @@ $(package)_cxxflags=-std=c++11 -fvisibility=hidden
 $(package)_cxxflags_linux=-fPIC
 endef
 
+# Fix unused variable in boost_process, can be removed after upgrading to 1.72
 define $(package)_preprocess_cmds
+  sed -i.old "s/int ret_sig = 0;//" boost/process/detail/posix/wait_group.hpp && \
   echo "using $($(package)_toolset_$(host_os)) : : $($(package)_cxx) : <cflags>\"$($(package)_cflags)\" <cxxflags>\"$($(package)_cxxflags)\" <compileflags>\"$($(package)_cppflags)\" <linkflags>\"$($(package)_ldflags)\" <archiver>\"$($(package)_ar)\" <striper>\"$(host_STRIP)\"  <ranlib>\"$(host_RANLIB)\" <rc>\"$(host_WINDRES)\" : ;" > user-config.jam
 endef