Style addresses

Style addresses

This changes gdb to style addresses.

gdb/ChangeLog
2018-12-28  Tom Tromey  <tom@tromey.com>

	* ui-out.h (enum class ui_out_style_kind) <ADDRESS>: New
	constant.
	* ui-out.c (ui_out::field_core_addr): Add styling.
	* stack.c (print_frame): Add styling.
	* printcmd.c (print_address): Add styling.
	(print_address_demangle, info_address_command): Likewise.
	* cli/cli-style.h (address_style): Declare.
	* cli/cli-style.c (address_style): New global.
	(_initialize_cli_style): Register new commands.
	* cli-out.c (cli_ui_out::do_field_string): Update.

gdb/testsuite/ChangeLog
2018-12-28  Tom Tromey  <tom@tromey.com>

	* gdb.base/style.exp: Update test to check for address styling.