NIFI-8132 Added FileDigestUtils in nifi-nar-utils to avoid dependency on nifi-utils
NIFI-8132 Removed unused imports from NarUnpacker
NIFI-8132 Removed MD5 references from FileUtils documentation
NIFI-8132 Replaced StringBuffer with StringBuilder and made new DigestUtils classes final
NIFI-8132 Replaced Collections.sort() with Stream.sorted()
Signed-off-by: Nathan Gough <thenatog@gmail.com>
This closes#4788.