Correct info fro FreeBSD
Correct info fro FreeBSD

1. Replace the outdated reference to "vritualenv", "see below" -> "see above".
2. Replace the awkward sentence (partially incorrect) about installing on FreeBSD. 
It can be installed via different ways: "pkg" is not exclusive. I am not aware of any reason why it canNOT be installed from ports. Some people prefer build and install everything from ports. (The previous version of the description implies that ports cannot be used.)
letsencrypt/letsencrypt,letsencrypt/letsencrypt,lmcro/letsencrypt,stweil/letsencrypt,jsha/letsencrypt,lmcro/letsencrypt,stweil/letsencrypt,jsha/letsencrypt