Create new acs.repository.usage.sessions data collector

Acceptance Criteria:

• Collector for acs.repository.usage.sessions has been implemented in community
• Javadoc is present and the collector follows the best practice of being self-describing
• Tests are present.

Details:
Collector ID: acs.repository.usage.sessions
Frequency: Hourly
Data Collected:

• Active tickets (user sessions)

Implementation Considerations:
org.alfresco.repo.admin.RepoServerMgmt?

The active tickets can be seen in the admin console /alfresco/service/enterprise/admin/admin-activesessions

Check that the ticket count represents tickets in a cluster and not just in one node of a cluster. If the ticket count is per cluster node then this collector will need to send data for each cluster node.