Rough working version. Includes complex triggers and selective showing of whois info.

More detail on the commit:

- This spice is now triggered by either a) naked domains (i.e. query containing only a domain), or b) queries that contain a domain as well as certain keywords at the beginning or end of the string.

- The handle() function now correctly parses the domain, even if other keywords are in the query.

- The API username and password are now handled by environment vars, rather than hard-coded.

- If a domain is available, this fact is always shown to the user.

- If a domain is not available, whois info for that domain is shown only when whois-related keywords are present. Whois info is NOT shows for naked domains, because a user who types 'google.com' probably doesn't want to see whois info (but may want to see a message when that domain happens to be available).

- More whois information is now shown. This required unnesting some fields within the API output and doing some basic formatting on date strings.

- Encapsulated more code into function.