In multitenant app, drop all nodes for big topologies

[bboreham]

As a protection against overloading the app server, drop topologies that have really large node counts. In practice we only see this with runaway numbers of zombie processes.

I've only wired this in to the AWS collector, since that is where we felt the pain.

Also some refactoring of the AWS collector parameters where the duplication started to get annoying.

[satyamz]

@bboreham I am looking into this,
How do I run multi tenant app ? I mean apart from options -app.collector & -app.collector.s3, do I need to setup anything?
I am setting up dynamodb & s3 in my aws account.

[bboreham]

@satyamz thanks for looking.
I think you also need --app.userid.header=X-Scope-OrgID to set how it finds the tenant ID.