Updates README.md escaping backtick in commands
Merge pull request #66 from mingliangfeng/master

Update README.md
Merge pull request #60 from awilliams/patch-1

Updates README.md escaping backtick in commands
Support FreeBSD date utility

Both FreeBSD and OSX use the POSIX date utility.
Merge pull request #69 from pigmonkey/backup-freebsd

Support FreeBSD date utility