Modify reporting to be able to present rolled up organization numbers

Many organizations which we create will have no direct usage, and only get usage by virtue of having sub-organizations.

In order to present usage information we need to:

* Bubble up activity numbers and unique values like user counts etc.
* Bubble down paying status (we should talk about this!)

## Definitions of "bubbling"

* We have a parent and child relationship
* Numbers can be added to the parent from the children ("bubbling up")
* Numbers can be added to the children from the parent ("bubbling down")
* These numbers are "bubbled"
* Numbers which are calculated directly on an entity without relation to it's parent or children are "non-bubbled"

## Some conclusions

### Paying isn't something we should concern ourselves with in Report at all

* This is a matter for Sales to work out
* We should therefore _not_ do anything for this work to modify paying
* We should as a separate matter, remove anything from Report to do with paying
* However viewing linked deals in Report is still useful

### Other activity numbers bubble-up as we thought

* Users, teacher and annotations should bubble up from children to parents

### We never want to see non-bubbled numbers

* There is no reason to display non-bubbled numbers
* All places you can see an activity metric for an organization, you are seeing bubbled numbers
* This also goes for Hubspot export

### Most reports over "Organizations" really are only concerned with root organizations

* If you are searching for or viewing orgs, you should be able to find what you are looking for
* In most other reports that count, or present "Top X Orgs" we really only want to be looking at root orgs
* Root orgs have no parent above them
* It might be worth having a think about, and agreeing, some different names for things:
* Organizations which are explicitly at the top of the tree ("top level organizations"?)
* Organizations which are not at the top of the tree ("sub-organizations"?)
* A word for organizations at any position in the tree ("organizations"?)