`GraphView` button layout and window size

[reelmatt]

I would suggest a few more changes to make the GraphView a little more user-friendly.

1. Increase the size of the modal pop-up. It will never be large enough to handled the biggest data sets. Right now it has a max-width of 500px (at smaller breakpoints it increases to the window size).
2. Before data is loaded, the button options are currently 'Accept' and 'Load'. I would propose changing 'Accept' to 'Cancel'.
3. After data is loaded and viewing it graphically, the button text is 'Accept'. I would propose changing this to 'Done' or 'Okay'.
4. Cell highlighting alternates by row and column (e.g. A1 is shaded, B1 is not and the opposite for the second row). I would propose cell shading is constant by row (e.g. row 1 is shaded, row 2 is not), without alternating by column.

[diegostruk]

Another suggestion: clicking on graph view button in a node that does not have data loaded should give a popup saying that there is no data to view (or have the graph button disabled).