Add support for VendorSpecific TLVs in Service Flow configuration.
Fix handling of 0x0a value in vendorspec()

Add the 's' modifier to substitutions in vendorspec, otherwise
the value of 0x0a is treated as a newline and doesn't match.
Use Digest::SHA instead of Digest::SHA1

In newer perl versions Digest::SHA is builtin
and is a drop-in replacement for Digest::SHA1.