Added URL as a property on the frontend

[BharatKalluri]

Added URL as a proprty option on the frontend

Summary

Takes #84 as a reference 😅 and adds a URL prop on the frontend. Seems like its already a part of propertyValue

Ticket Link

#37

I had one small question, eventually will focalboard have validations on the text in the propertyValue?

[mattermod]

Hello @BharatKalluri,

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[chenilim]

Thanks for the PR @BharatKalluri! Let's hold off on this one for now.

Currently the 'text', 'number' and 'email' properties all map to an Editable text field. They should instead map to distinct controls with validation, etc. For instance, we should not be able to enter letters into a number field. Emails and URLs should be validated.

[jespino]

@BharatKalluri I added a property validator mechanism in master, do you mind to merge master in your branch and add the url validator there? With that, I think this PR is ready to go.

[BharatKalluri]

Sure, I'll be adding the URL regex from https://www.urlregex.com/

The regex for a URL is given to be
/((([A-Za-z]{3,9}:(?:\/\/)?)(?:[\-;:&=\+\$,\w]+@)?[A-Za-z0-9\.\-]+|(?:www\.|[\-;:&=\+\$,\w]+@)[A-Za-z0-9\.\-]+)((?:\/[\+~%\/\.\w\-_]*)?\??(?:[\-\+=&;%@\.\w_]*)#?(?:[\.\!\/\\\w]*))?)/

[jespino]

Now looks good to me. Thanks! 🎉