CLOUDIFY-2251

Write to a file an indication after celery agent was restarted
CLOUDIFY-2251

Add installation of kv_store plugin on agent
CLOUDIFY-2251

Switch plugin installer version to feature branch
switched plugin installer to develop branch
Merge pull request #6 from CloudifySource/feature/CLOUDIFY-2251_transfer_installed_plugin_knowledge

agent installer will install kv_store plugin on each agent machine