API Key support

[andaaron]

Is your feature request related to a problem? Please describe. JFrog Artifactory has API key support. The request I got is for Zot to implement something similar, so that LDAP users don't have to use their LDAP passwords in scripts which they may share with others.

Describe the solution you'd like A user should be able to generate an API Key to access the Zot API. Ideally this could be done from the web interface. When authenticating with this key, a script would benefit from (a subset of?) the user's permissions.