Internal function to validate all required parameters for email sending.
Usage
.validate_email_params(to, from, visitor_name, visitor_email, msg)
Arguments
- to
Recipient email address
- from
Sender email address
- visitor_name
Name of the person sending message
- visitor_email
Email of the person sending message
- msg
Message content
Value
List with valid (logical) and errors (character vector)
