Make bootstrap scripts work more reliably

* Set -e so that we don't continue blindly ploughing on after an error.
* Don't try running services that have not yet been installed
* Fix some incorrect string escaping in vagrant/bootstrap.sh
* Fix environment variable setting in vagrant/bootstrap.sh (appending to
  ~/.bashrc doesn't work for scripts, since .bashrc starts with
  `[ -z "$PS1" ] && return`)
* Remove verbosity from unpacking archives
Merge pull request #18 from ept/bootstrap-scripts

Make bootstrap scripts work more reliably
SAMZA-152 Add samza-kv example to wikipedia-stats
SAMZA-139 bin/grid should work if invoked as ./grid
Merge pull request #22 from ept/SAMZA-139

SAMZA-139 bin/grid should work if invoked as ./grid
Merge pull request #21 from ept/SAMZA-152

SAMZA-152 Add samza-kv example to wikipedia-stats
Revert "Merge pull request #21 from ept/SAMZA-152"

This reverts commit 518f89d3f5b019d430d608349c03fc2e59ed1088, reversing
changes made to 79f31224308f0e2e39e5e6851ebb4535611e25f6.
SAMZA-153 Make bin/grid cache downloads in ~/.samza
Explicitly tell YARN NM to find RM on localhost
Merge pull request #20 from ept/yarn-network-config

Explicitly tell YARN NM to find RM on localhost
Merge pull request #23 from ept/SAMZA-153

SAMZA-153 Make bin/grid cache downloads in ~/.samza
reverting yarn-site.xml change until SAMZA-154 is resolved.
SAMZA-155 Automatically set JAVA_HOME on Mac OS
Merge pull request #24 from ept/SAMZA-155

SAMZA-155 Automatically set JAVA_HOME on Mac OS
upgrade system admin name for wiki consumer as part of SAMZA-146
making 'basename' call compatible with old coreutils package which don't support '-s'
Merge pull request #26 from opsmekanix/master

Basename shell-out needs to be compatible with old coreutils package not supporting "-s"
upgrade grid script ot 2.10
fully upgrade hello-samza to 2.10
't use -e for bash because kafka-server-stop.sh will return non-zero if no kafka brokers are running, which is valid when you first run bootstrap. this fails the whole script with -e, whcih is not right.