• Simplify multiple sentences to remove the words: furthermore, also, ...
• Fix typo's, IP address is redirect_port example & visible double space

after sentence stop

• Restructure TSO comment together with the in-kernel NAT instance paragraph
• Add kernel option for libalias full functionality
• Unify engine/facility/... to facility

Submitted by: Dries Michiels (driesm.michiels_gmail.com)
Approved by: bcr@
Differential Revision: https://reviews.freebsd.org/D23426