REMAIN
     Returns a pattern matching any string that starts at the current
     character position and continues to the end of the current line.  The
     pattern returned does not cross line boundaries.
  Syntax
     pattern := REMAIN
  Example
     pattern_runoff := LINE_BEGIN + "." + REMAIN;
     Stores in the variable PATTERN_RUNOFF a pattern matching all lines that
     have a period at the beginning of the line (such as RUNOFF commands).