Function usage:
  ECHO(text [, attrs
  [, inline [, dest]]])
Command usage:
  /ECHO [-peA] [-aattrs]
  [-w[world]] text
  /_ECHO text
Displays text on the tfout stream (i.e., the screen, usually), unless otherwise redirected by options.
Options and arguments:
-aattrs
  attrs
	-p
  "on" or 1
	@{attr}" strings as commands to
        set attributes inline.
        "@@" strings are interpreted as "@".
	"@{n}" or "@{x}" will
        turn attributes off.
	See also: decode_attr().
  -wworld
  "wworld"
	-e
  "e"
	"o"
	-A
  "a"
	The command form is usually more convenient, but the function form is the only way to echo text with leading or trailing spaces. Remember that "-" by itself can be used to mark the end of command options, in case text begins with "-".
/_echo is more efficient than /echo, so it is better for use in heavily used macros that don't need all the options of /echo.
When echoing to the tferr stream, if no attrs are specified, text will be echoed with the "E" attribute.
Example: Both of these commands
  /test echo("@{u}Hello@{n}, world!", "BCred", 1)
  /echo -aBCred -p @{u}Hello@{n}, world!
  echo the following line, with "Hello" underlined, and the whole line bold red:
  Hello, world!
Echoed text is not matched against triggers. To do that, use /trigger.
See: attributes, worlds, fwrite(), pad(), tfio