message: correct make flags directive to apply to C++ files only
diff: # it under the terms of the MIT license. See LICENSE for details.
  #
  -AM_CPPFLAGS = -Wall -g3 -ggdb -std=c++11 -I$(top_srcdir)/external/http_parser -I$(jalsoninc) $(libuvinc)
  +AM_CXXFLAGS = -Wall -g3 -ggdb -std=c++11 -I$(top_srcdir)/external/http_parser -I$(jalsoninc) $(libuvinc)
  AM_LDFLAGS=-lpthread
  