Get and send data concurrently #48
Description
At the moment, we collect all of the data (usage data in particular) and then POST it all. I'm sure we can do things more quickly with async or threads, if we need to. This could bring memory and time benefits. Low priority though.
Note that data is an ItemPaged object with a by_page() method so we could get items in chunks (supposedly often ~1000 items, according to Microsoft docs). However, it isn't entirely clear from the docs whether this offers any real benefit, since the ItemPaged handles paged items for you and can be treated like a single iterator to a big list.