[sugar] icon assistance/validation

[Eben Eliason]

>  oh yeah -- i forgot to mention the defaults.  i don't think
>  they're all that useful (hence my notion of guessing them),
>  because there there are a lot of competing suggested values, none
>  of which include "#666666", that i can find :-).

This is quite true.  On the other hand, these are the values which I'd
*like* to standardize.  The design philosophy for uninstantiated
activity icons is that they are merely outlines, with no fill, until
activated.  The (#666666, #ffffff) pair will be the default appearance
of the activity icons before they are launched within Sugar, and it
would be nice to mirror this, from this point forward, in the wiki
pages.  And, for that matter, once I get to updating the wiki with the
script and instructions, I'll suggest these as the defaults.

Guessing is still an idea worth attempting, but I'm not sure how
accurate it can function except in the simplest cases.

- Eben