Chunk server: ensure that the client threads are shutdown in the case of errors in start sequence.
Meta server: emit trace log message at the info level before creating new file system.
Test scripts: create test script in order to facilitate testing qfs with hadoop single node mode. The script is intended to be executed in hadoops install directory, in place bin/hadoop with "jar" and "fs" arguments. The assumption is that the sample saervers are already succeffully installed and ruuning.
Test scripts: qfs hadoop test fix help message typos..
Examples: implement -u / -auth sample_setup.py option to start chunk and meta server with authentication enabled, and create corresponding QFS "client" configuration file. Quote all shell arguments. Add client and certs sections to the sample servers configuration file.
Examples: sample servers create new file system only if install requested and log and checkpoint directories are empty, the primary intention is to avoid creating a bad / dangerous example where the meta server is always started with -c / crate flag. Create QFS client default configuration file. Create default user directory to facilitate hadoop testing. Emit web ui url, and qfs tool command line after completing the installation simplify initial qfs "install to try".
Hadoop shim: use isDir instead of isFile to make the it work with older hadoop API.