Add five new icons

[grooveborg]

Added icons for:

• Aruba (the Instant On issuer specifically, but the icon can probably be used for other Aruba accounts)
• Con Edison
• Parsec
• SendGrid (issuer is blank by default, needs to be manually added in-app)
• Synology DSM (issuer is blank by default, needs to be manually added in-app)

I had to modify the GenerateIssuerIconAssets.sh script to work with ImageMagick instead of sips since I am using Ubuntu.

Thank you for the app!