* opts.c: Include diagnostic-color.h.
	(common_handle_option): Handle OPT_fdiagnostics_color_.
	* Makefile.in (OBJS-libcommon): Add diagnostic-color.o.
	(diagnostic.o, opts.o, pretty-print.o): Depend on diagnostic-color.h.
	(diagnostic-color.o): New.
	* common.opt (fdiagnostics-color, fdiagnostics-color=): New options.
	(diagnostic_color_rule): New enum.
	* dwarf2out.c (gen_producer_string): Don't print -fdiagnostics-color*.
	* langhooks.c (lhd_print_error_function): Add %r "locus" and %R around
	the location string.
	* diagnostic.def: Add 3rd argument to DEFINE_DIAGNOSTIC_KIND macros,
	either NULL, or color kind.
	* diagnostic-color.c: New file.
	* diagnostic-color.h: New file.
	* diagnostic-core.h (DEFINE_DIAGNOSTIC_KIND): Adjust macro for 3
	arguments.
	* doc/invoke.texi (-fdiagnostics-color): Document.
	* pretty-print.h (pp_show_color): Define.
	(struct pretty_print_info): Add show_color field.
	* diagnostic.c: Include diagnostic-color.h.
	(diagnostic_build_prefix): Adjust for 3 argument DEFINE_DIAGNOSTIC_KIND
	macros.  Colorize error:, warning: etc. strings and also the location
	string.
	(diagnostic_show_locus): Colorize the caret line.
	* pretty-print.c: Include diagnostic-color.h.
	(pp_base_format): Handle %r and %R format specifiers.  Colorize strings
	inside of %< %> quotes or quoted through q format modifier.
c-family/
	* c-format.c (gcc_diag_char_table, gcc_tdiag_char_table,
	gcc_cdiag_char_table, gcc_cxxdiag_char_table): Add %r and %R format
	specifiers.
cp/
	* error.c (cp_print_error_function,
	print_instantiation_partial_context_line,
	maybe_print_constexpr_context): Colorize locus strings.

From-SVN: r197842