Remove directories which are not present in CDAP 2.5
Remove files, remove vim, and use tail instead of insecure ssh
Clean up SSH remnants
Use ENTRYPOINT and fix tail
Merge pull request #779 from caskdata/feature/remove-missing-dirs-dockerfile

[Docker] Feature/remove missing dirs dockerfile
Merge remote-tracking branch 'origin/release/2.5.0' into feature/cdap-895