CLASS-> STYLE-> OFFSET - documentation of the meaning of -99

[havatv]

The current documentation for CLASS-> STYLE-> OFFSET (in http://mapserver.org/mapfile/style.html) is as follows:

OFFSET [x][y]
    Offset values for shadows, hollow symbols, etc ...

In order to include the importent special "x -99", I propose to change it to something like:

OFFSET [x][y|-99]
    Offset values for shadows, asymmertical lines symbols, hollow symbols, etc.
    If OFFSET is specified for a line and y is given the value -99, the rendered line will be offset x units perpendicular to the direction of the line.  For any other y value, the offset will be independent of the line direction.

[havatv]

Fixed in r11494.