Add RuleSetChanged event to events streamed to SonarLint

Actions that trigger an event:
Activating a rule in a Quality Profile (qualityprofiles/activate_rule)

Deactivate a rule in a Quality Profile (qualityprofiles/deactivate_rule)

Reassigning a Quality Profile from one project to another (qualityprofiles/remove_project, qualityprofiles/add_project)

Bulk activation of several rules in a Quality Profile (qualityprofiles/activate_rules, qualityprofiles/deactivate_rules) -> is using ruleActivator.activate and ruleActivator.deactivate, so it's working out of the box from the POC but it will trigger several events.

Change in the severity of a rule in a Quality Profile (qualityprofiles/activate_rule with "severity" param)

Change in a rule parameter attached to a Quality Profile (qualityprofiles/activate_rule with "params" param)

The events should only be streamed to a SonarLint client when they relate to the Project and Language in which SonarLint client is interested.

Event payload:

data: {
  projects: [projectKey1, projectKey2, ..]
  activatedRules: [xxx, yyy],
  changedRules: {
    {
      key: xxx, 
      overriddenSeverity?
    },
    {
      key: bar, 
      params?: [
        key: x,
        value: y
      ]
    },
  ],
  deactivatedRules: [zzz, foo]
}