Custom metadata // Bring your own Metadata

[vikiival]

Is your feature request related to a problem? Please describe.
As user I would like to add custom traits to the attributes array.

Describe the solution you'd like
Have button along with to add custom metadata

[vikiival]

Currently to we pass tags to the metadata (check example here) which is basically Attribute[].

The goal here is to have a Collapse with an additional form which will contains all properties of the Attribute (display_type, trait_type, value). After submit a form should be cleared and the "new" tag should be added to the existing <TagInput/>

Checks:

• create separated component (Attribute Form)
• create separated component (Attribute form within Collapse)
• on submit clear attribute form and add the tag to the tag input values
• make sure that it is pinned correctly

[yangwao]

Related #417