Add install-only recipe[v2]

Added functionality to only create zookeeper user and install files with
a new recipe 'install' which is just a subset of the default recipe.
The default recipe continues to work as it did before.

This is a respin of the previous patch with a couple of changes to make
merging easier for upstream.

Signed-off-by: Scott Lovenberg <scott.lovenberg@gmail.com>
Merge branch 'master' of https://github.com/Gazzonyx/chef-zookeeper

Signed-off-by: Scott Lovenberg <scott.lovenberg@gmail.com>

Conflicts:
	README.md
	metadata.rb
	recipes/install.rb