Added a comment about 5.3 compat files (GitHub #21)
Added a comment about 5.3 compat files (GitHub #21)

maxmind/GeoIP2-php,g9007676/GeoIP2-php,maxmind/GeoIP2-php,Shemtek/GeoIP,cemoulto/GeoIP2-php,g9007676/GeoIP2-php,cemoulto/GeoIP2-php