PAS-4: HTTPS Referrer Search should only match on the Referrer field

The current means of searching for HTTPS sites within HTTP referrers is overly broad, the HTTP CSV is simply grepped.

As a result, if a site has a cookie with a value matching the string we're searching for it will be matched and included in the known SSL paths section.

For example

1447885734.980645000    192.168.3.64    23.235.43.239   58834   80      www.wired.com   GET     /wp-content/uploads/2015/11/black-box-600x338-e1447374320621.jpg        http://www.wired.com/2015/11/carnegie-mellon-denies-fbi-paid-for-tor-br
eaking-research/ Mozilla/5.0 (Linux; Android 4.4.2; en-gb; SAMSUNG GT-I9505 Build/KOT49H) AppleWebKit/537.36 (KHTML, like Gecko) Version/1.5 Chrome/28.0.1500.94 Mobile Safari/537.36    original_referrer=https://www.google.co.uk/;_ ga=GA1.2
.2062192190.1409172610;

Would match a search for https://www.google.co.uk despite not actually being related.

Note: the fix for PAS-2 _might make this point moot