add disclaimer for collections that are non-constodial

[evanwill]

Disclaimer on About page plus update "rights" field to say "not held by Spec"

• cccidaho
• archivalidaho

[evanwill]

rights something like: In Copyright - Educational Use Permitted. Please note these materials are not held by University of Idaho Library Special Collections and Archives. For more information, please contact the institution listed in the Source.

disclaimer something like:
{% include feature/alert.html color="warning" text="Please note: materials in this digital collection are not held by University of Idaho Library Special Collections and Archives. Additional information or higher quality images may not be available. Please consult each item's information to find the holding institution." %}