Add alternate logo functionality

[obasekietinosa]

Allow multiple logo versions for organizations.

Example use case would the square versions or dark color versions of the logos.

Proposed implementation would be to add a new field to logos.json entries, say alternates and then have the app render a "click here to see alternate versions" below the image that brings up a modal with alternates to download.

[prezine]

This makes sense,
first @Odusanya Can you approve the pending pull request of logos

[fathermerry]

@obasekietinosa Sorry for the super late reply.

I agree 100%. Feel free to make a PR if you have the time. cc @aeadedoyin

[solamichealolawale]

I agree with @obasekietinosa advice, but I think a carousel or slider of logos (if alternate is present) would be appropriate with the same functionality on each of the images.