Fixes #105 - init_defaults doesn't work properly with java opts values

Adding single quotes to the augeas set command allows users to pass in
ES_JAVA_OPTS with double quotes. See #105 for more information.

Update tests and add ES_JAVA_OPTS to assertions
Run plugin exec commands as elasticsearch_user
Move exec user attribute to master Exec
Update node definition files to use docker. Remove old configs
Update Gemfile to make use of groups
Improve spec helper

- Add puppet dependencies via scp to avoid downloading them all the time
- Moved all dependencies for augeas to node files so remove them here.
Improve tests

Add random cluster name to avoid weird issues
Add some more basic tests to ensure it all works.
Improve travis file to avoid loading things we don't need.
Improve rakefile
Improve gemfile handling and different jobs
Add junit report gem
Merge pull request #109 from elasticsearch/feature/beaker-docker

Feature/beaker docker
Merge pull request #108 from afx114/plugin_permissions

Run plugin exec commands as elasticsearch_user.  Fixes #107
Merge pull request #106 from dblessing/fix_sysconfig

Add single quotes to value. Fixes #105
fix plugin dir rights
Update gitignore for new gemfile path
Pin Rake for Ruby 1.8.7

The latest Rake update requires Ruby >= 1.9. This update
fixes the failing 1.8.7 tests by pinning Rake to the last
supported version on ruby 1.8.7.
fix puppet-lint warning
Improve Readme based on PR #102