Auto-legend entries
-------------------

This module allows you to use the **-l** option to specify an automatic legend entry.
This option is available for lines or symbols only.  If there is no size specified
(which is always true for lines) or if the symbol size is computed from other information
(which may be true for some symbols deriving size from other input columns), then you need
to supply a legend size (i.e., length of a line symbol) via the **+S** modifier.
