PR binutils/1437

PR binutils/1437
* cxxfilt.c (flags): Remove DMGL_TYPES;
  (long_options): Rename --no-types to --types.
  (usage): Likewise.
  (demangle_it): Add a comment describing why _ and $ prefixes are skipped.
  Use printf rather than puts to emit the demangled output in order to avoid
  emitting a new line character.
  (main): Have the -t flag enable type demangling.
  Emit a newline after every demangled command line argument.
  Copy whitespace from stdin to stdout.
* doc/binutils.texi (c++filt): Document the change to the -t switch.
  Document why demangling names on the command line is slightly different
  to demangling names read from the standard input.