Updates ExternalURL info

[ph0ph0]

Updates ExternalURL info to make its usage more explicit

Closes: #???

Description

The description for ExternalURL was unclear. This PR hopes to make its usage more explicit by expanding on the example.

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For contributor use:

• [ ] Targeted PR against master branch
• [ ] Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• [ ] Code follows the standards mentioned here.
• [ ] Updated relevant documentation
• [ ] Re-reviewed Files changed in the Github PR explorer
• [ ] Added appropriate labels

• [ ] Update the version in package.json when there is a change in the smart contracts

[bshahid331]

Maybe include an example so its more clear as well?

[joshuahannan]

Addressed this in #163