Add support for creation of class 4 ticket codes

[elv-serban]

The current elv-live tool can create ticket codes for the 'class 5' NTPs (backed by authd) but not for class 4 (contract-based, and supported by the elvmaster API).

Added option --otp_class which can take values 4 or 5

For the class 4 NTPs:

• added support for email-bound tickets (by specifying --emails file-containing-emails)
• added support for generating embed URLs (by specifying a base URL to add code to --embed_url_base ...)

Example:

./elv-live tenant_tickets_generate iten4CEZmYniuxBsmbNu7rUK3r4DUPg6 QOTPhc5E53XZE8x --quantity 3 --otp_class 4

./elv-live tenant_tickets_generate iten4CEZmYniuxBsmbNu7rUK3r4DUPg6 QOTPhc5E53XZE8x  --otp_class 4 --embed_url_base 'https://elv-tv4-embed.web.app/?p=&net=main&cid=iq__3WMwaTLKbrRS4EE21pCMj4Qk92Q7&type=v&ptk=&ten=iten4CEZmYniuxBsmbNu7rUK3r4DUPg6&ntp=QOTPhc5E53XZE8x&ct=h' --quantity 3

./elv-live tenant_tickets_generate iten4CEZmYniuxBsmbNu7rUK3r4DUPg6 QOTPhc5E53XZE8x  --otp_class 4 --embed_url_base 'https://elv-tv4-embed.web.app/?p=&net=main&cid=iq__3WMwaTLKbrRS4EE21pCMj4Qk92Q7&type=v&ptk=&ten=iten4CEZmYniuxBsmbNu7rUK3r4DUPg6&ntp=QOTPhc5E53XZE8x&ct=h' --emails emails.txt