make PIPE_DIR overridable
Modified error handling around nodetool to reduce silent failures
Replace "-s init stop" with halt()
Merge pull request #218 from tolbrino/tb/conf-pipedir

make PIPE_DIR overridable
Merge pull request #222 from srstrong/master

Modified error handling around nodetool to reduce silent failures
Merge pull request #224 from jaydoane/replace-init-stop-with-halt-in-bin-dot-dtl

Replace "-s init stop" with halt()