sec - the cmusic section command

This command has the general form:

    sec T;

or just:

    sec;

If given with a time T which is greater than the ending time of any
note, extra silence is generated up to time T.  If no time is given, or
if T is less than the ending time of any current note, all notes are
first finished.  Then the current action time (p2) is reset to 0 and
the score continues.

Example:
    .
    .
    .
    note 3 toot 4 ... 
    note 4 honk 1 ...
    sec;		{ends section at time 7}
    note 0 toot 1 ...   {starts new section at time 7}
    note 1 honk 2 ...   {sounds 8 seconds after beginning}
    sec;
    ter 2;		{generates 2 seconds of silence at the end}
