Our DMARC record parser made the assumption that the entire DMARC record

was quoted in a single string. This is the usual way DMARC records are

composed. However, a case came up where a customer had a record in the

form of:
"v=DMARC1;" "p=reject;" "pct=100;"

Our parser couldn't handle this. The p key was not found, and instead

we had a " "p key.
This was due to us grabbing the entire text record, rather than the

individual strings in the record. We now grab those strings instead and

join them together, giving us a nice, normalized text string we can work

with.
To avoid issues with legacy cached data, the cache key has been renamed

from dmarc-record-<host> to dmarc-record:<host>. This will

invalidate all old records and force a re-fetch and parse of any DMARC

records.

Unit tests pass.
Tested this against a known DMARC record that we failed to parse.

Verified the results were correct.