Giv documentation failures

[Multimath]

At URL http://giv.sourceforge.net/giv/giv.html

• The example for $quiver_color in the table of properties is wrong : copy-paste error
• There are two entries for $noline in the table of properties and both text descriptions contain language errors
• There is no entry for $line in the table of properties
• The entry for $def_style in the table of properties isn't explicit enough to document how multiple properties are wrapped up into the one style: should they be appended on the same line or should multiple $def_style lines with the same style name be used?
• There seem to be a lot of new properties in the code which are undocumented in the table of properties...

[dov]

I have fixed most of the issues. There are still a few keywords that don't work as they should and I have left them out of the documentation.

Thanks for the feedback!