Ticket ID matching does not support extended format.

[mikepea]

We need to find ticket IDs in plaintext, for a couple of reasons:

• It means we can do the drill-down from the TicketShow page, where ticket IDs are in the comments, blockers, ... fields
• The TicketList page currently works on a template, so we actually pull the ticketID out from the raw string.

@Feriority found this in #23 -- https://confluence.atlassian.com/jira/changing-the-project-key-format-192534.html -- which indicates that we need to perform a better match.

Also, it's probably worth adding some logic to the TicketList page to pull the ticket IDs out via the API response, rather than via findTicketIdInString(). More robust, innit.