LIMS-1163: Improve error message when token is invalid

[ndg63276]

JIRA ticket: LIMS-1163

Summary:

Users complain of not being allowed to print an air waybill after booking a shipment into Diamond.

Changes:

• Specify in the error message generated whether this is because the one time token is too old, or non-existent
• Add user agent and timestamp to the error message generated
• Allow increasing of 10 second age limit with an optional config variable

To test:

• Generate an AWB for a shipment, check can view it from the shipment page
• Set a $max_token_age = -1 config variable and check the error generated (delete it afterwards)
• View a visit pdf report and CSV download from /visits page, as these also use the sign function

[MattPrit]

I'm not sure that we would want to tell the user this. Perhaps we should, if a valid token is not found, return a more generic message to the user, e.g. "Invalid one-time authorization token, please go back and try again...", but log the reason internally.

out of date