Layout improvements

[ptbrowne]

Fix #334

• Remove the stepper (Process-Navigation) and add Call to actions. See invision doc here
• Add process bar on top (Turn the red bar CI element into a process bar. See Invision doc here
• Turn Back and Next Button into text links and put them on the outer left and right See Invision doc [here]
• Keep “Publish” Button as Button but change the label to "Publish this visualization". See invision doc here
• Change color of "Back to the data list" to grey #757575. See Invision doc here
• Published chart: Change Share and Embed buttons from links to buttons. See invision doc here
• Change Color of “Create new visualisation” and "Copy and edit this visualization" to grey #757575.
• Change label of Copy visualization to "Copy and edit this visualization

[AnninaWalker]

Looks great @ptbrowne ! Love it! Only one minor thing: I think, we can get rid of the "Choose another dataset" as we have the Back Button now on top

[ptbrowne]

Agreed, done 👍

[ortnever]

Now that we are navigating with the "back" and "next" button I don't find it logical to go back to the page "all datasets" when we are on the page "Select a chart type"
The previous step in this case would be the data preview and not the list of datasets.
I understand your shortcut but I find it not very transparent.