Contribution Page Widget restructure and cleanup

[mlutfy]

Overview

Restructure the layout of the Contribution Page Widget configuration:

• Remove the top "Configure Widget", other tabs do not have this
• Checkbox "Enable Widget?" renamed to "Enable the Widget"
• Removed the warning about Flash
• About : now optional
• Show the preview at the top, not in the middle (the colours were oddly separate from the snippet, while being rather important).
• Colours:
  • No more accordions (ideally the colours would be in a grid, but I could not find a class for it)
  • Moved above the "About" text area because the textarea is huge and it's not really important.
• "Background Color Top Area" renamed to "Title Background Color"
• Colours are not required, because in the Contribution Progress extension, I don't need all of them (I'll hide the non-required ones), and besides, it's difficult to make them empty.
• Removed redundant "Save and Preview" buttons which did nothing special
• Remove some capt'n obvious help messages

Before

After

Technical Details

I cheated on the CSS of the widget, because Riverlea does not have what I need here, and it looked a bit weird. This looked better in the old Greenwich, but I don't think it's important enough to spend more time on it.

Comments

Admittedly not perfect, but better than before.

[civibot]

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[mlutfy]

Random WIP for the Contribution Progress extension, which provides a different visual:

[mlutfy]

Feedback from @samuelsov : remove the repeat word "Color":

I also tweaked a help message, since the "Save and Preview" button is gone:

Before: