SYNOPSIS
	string read_file(string file, int start, int number)

DESCRIPTION
	Reads lines from file.
	If <start> is not given or 0, the file is read from the
	beginning, else from the numbered line on.
	If <number> is not given or 0, the whole file is read, else
	just the given amount of lines.
	If <start> would be outside the actual size of the file, 0 is
	returned instead of a string.

SEE ALSO
	read_bytes(E), write_file(E)
