Add ability for any attribute to include a link. #489

Description of your request
Add ability for any attribute to include a link.

Describe the solution you'd like
Similar to the Scientific Name attribute, which is text+url. Add the ability for any attribute to include a(n optional) url, i.e. have:

• boolean+url
• string+url

maybe also

• int+url
• float+url
• date+url

In particular I'm most interested in bool+url and text+url.

Describe alternatives you've considered
Creating a boolean and additionally creating a string attribute in which I paste the url.

Additional context
For example, we keep track of which plants are toxic to cats. We use the ASPCA data as a source of trust.

It would be great to have the red No also hold the link.

I really want to thank you for creating this app, it is lots of fun and me and my partner are enjoying using it for our not so little collection of plants.