Apply colour to all visuals of the line class

[stonier]

This allows setting of the colour properties for a line in rviz (currently doesn't work). Refer to discussion in #820.

[wjwwood]

Thanks for putting this in a pull request @stonier, as I stated in #820 I don't know if this is the right solution, maybe @hersh or @acornacorn or even @dgossow might have some time to look at it/insight into what the correct solution would be.

[hersh]

I'm fine with it if it looks good. There are other examples of setting colors in rviz, and they do something like set one type of color to rgb and the other to rgb/2 or something. I don't think it will hurt anything regardless, especially if the old version doesn't work.

[wjwwood]

I wonder if it should not be more like this setColor in shape.cpp:

https://github.com/stonier/rviz/blob/line_visualization/src/rviz/ogre_helpers/shape.cpp#L125-140

[hersh]

@wjwwood probably so, yes. :)

[stonier]

From Shape - it's the american revolution II!

void Line::setColor( const Ogre::ColourValue& c )

I updated for consistency across shape and line. Tested and seems fine.

[wjwwood]

Awesome, lgtm.