Reduce gradients usage in new Wizard

[vogella]

I think the gradients in our wizard look bad and I suggest we reduce the usage of them.

IIRC I also saw a statement from @Michael5601 that this would also be faster, once his SVG support is implemented and used.

So IMHO without the gradients the wizard would look nicer and if upcoming SVG they would also faster to be loaded.

For an example without gradient, looks at the Maven wizards:

@BeckerWdf WDYT?

[vogella]

See also #2721

[merks]

It looks bad that the image touches the top. Is that related or just somewhat poor icon design?

[Michael5601]

These wizard icons are all very detailed. I think this is due to the larger size in which they are presented compared to all other icons. I am also in favor of simplifying them and this is also my opinion for all other icons too.
But for the wizard icons alone we won't see a significant performance improvement when using SVGs as they only have limited usage.

[vogella]

It looks bad that the image touches the top. Is that related or just somewhat poor icon design?

I think it is the icon design. Of course you can define a icon without gradients without starting at the top.

[BeckerWdf]

For an example without gradient, looks at the Maven wizards

This icon anyway does not comply to the current eclipse style guide. Even if we don't like the current style we should stick to it so that the application looks consistent...

[vogella]

Please link to the corresponding style guide section

[merks]

I'm not sure where this lives now:

https://www.eclipse.org/articles/Article-UI-Guidelines/Contents.html#WizSpecsSize_VDG

[laeubi]

I'm not sure where this lives now

Source: https://github.com/eclipse-platform/ui-best-practices
Deployed: https://eclipse-platform.github.io/ui-best-practices/