Missing validations

[samrocketman]

• Repository name: Only letters, digits, underscores(_), hyphens(-), and dots(.) are allowed and must start with an alphanumeric.
• remote.url is required and must be a valid URL.
• version_policy validation must be one of: MIXED, SNAPSHOT, RELEASE
• layout_policy validation must be one of: STRICT, PERMISSIVE
• write_policy validation must be one of: ALLOW_ONCE, ALLOW, DENY
• docker.http_port must be between 1-65535.
• docker.https_port must be between 1-65535.
• docker_proxy.index_type validation must be one of: REGISTRY, HUB, CUSTOM
• docker_proxy.index_url must be a valid URL.
• url.content_max_age validation must be an integer greater than -1
• url.metadata_max_age validation must be an integer greater than -1
• nuget_proxy.query_cache_item_max_age on nuget proxy >= 0.
• connection.retries >= 0
• connection.timeout >= 0