<para>Time span values encoded in unit files can be
written in various formats. A stand-alone number
specifies a time in seconds. If suffixed with a time
- unit, the unit is honored. A concatentation of
+ unit, the unit is honored. A concatenation of
multiple value with units is supported, in which case
the values are added up. Example: "50" refers to 50
seconds; "2min 200ms" refers to 2 minutes plus 200