Prefix enum symbols LOG_* with IM_, not to clash with system headers


server-tools/instance-manager/instance_options.cc:
  Prefix enum symbols LOG_* with IM_, not to clash with system headers
server-tools/instance-manager/parse.cc:
  Prefix enum symbols LOG_* with IM_, not to clash with system headers
server-tools/instance-manager/parse.h:
  Prefix enum symbols LOG_* with IM_, not to clash with system headers
server-tools/instance-manager/commands.cc:
  Prefix enum symbols LOG_* with IM_, not to clash with system headers