Moving ip lookup to GeoIP binary data files

MailWatch now uses binary data file instead of CSV file imported to database to perform ipv4 and ipv6 country lookup.
Also 3 different download method (CURL extension, fopen and wget via exec()) and 2 gz extraction methods (Zlib extension and gunzip via exec()) are implemented

Fix #60
return unique relays
Merge pull request #82 from mailwatch/geoip_binary_file

Moving ip lookup to GeoIP binary data files