docs - color issues

[danton267]

x = linspace(0,3*pi,200);
y = cos(x) + rand(1,200);
c = linspace(1,10,length(x));
scatter(x,y,[],c)

fig2plotly(gcf);

prints this error, and the resulting plot is not colored

Unrecognized function or variable 'numColor'.
We had trouble parsing the scatter object.
This trace might not render properly.

same with this:

x = linspace(0,3*pi,200);
y = cos(x) + rand(1,200);
sz = 25;
c = linspace(1,10,length(x));
scatter(x,y,sz,c,'filled')

fig2plotly(gcf);

---

for this one, the middle of the plot is supposed to be transparent, it is all one color

x = randn(1000,1);
y = randn(1000,1);
s = scatter(x,y,'filled');

distfromzero = sqrt(x.^2 + y.^2);
s.AlphaData = distfromzero;
s.MarkerFaceAlpha = 'flat';

fig2plotly(gcf);

---

this plot when translated to plotly becomes unreadable:

load seamount x y z;

fig = figure;
scatter(x, y, 10, z);

title('Undersea Elevation');
xlabel('Longitude');
ylabel('Latitude');

fig2plotly(gcf);

[gilbertogalvis]

This issues was fixed by PR #461

Here the results

Test code 1

Test code 2

Test code 3

Test code 4