Design: OpenAPI: Create new icons for Eclipse generator actions, wizards and files

[keithchong]

Codewind version: latest
IDE: Eclipse only

Description of the enhancement:
Currently, the actions and wizard banners in the Codewind OpenAPI tools for Eclipse have no icons. This shows that the tools are not fit and finished

Attn: Kim H.

I'm using existing icons from Eclipse in the interim. For example, this is what I'd to see in the context menu. Since the generator actions generate files/code, there should be a '+' overlay over the main icon. This should be consistent across all actions. (The first one does not have it):

Currently in the latest release:

[sishida]

Tagging @kimholmes to notify the design team.

[keithchong]

File icon:

[keithchong]

Interim wizard icons: