* [Stats API] Set API field names per spec
* fix jest tests
* fix api integration test
* trash the original metrics collector
- constantly accumulating stats over time does not align with the existing behavior, which is to reset the stats to 0 whenever they are pulled
* move some logic out of the collector types combiner into inline
- change the signature of sourceKibana
* Make a new stats collector for the API
- to not clear the data when pulling via the api
- fetching is a read-only thing
* isolate data transforms for api data and upload data
* no static methods
* remove external in bytes
* remove the _stats prefix for kibana and reporting
* update jest test snapshot
* fix collector_types_combiner test
* fix usage api
* add test suite todo comment
* reduce some loc change
* roll back mysterious change
* reduce some more loc change
* comment correction
* reduce more loc change
* whitespace
* comment question
* fix cluster_uuid
* fix stats integration test
* fix bulk uploader test, combineTypes is no longer external
* very important comments about the current nature of stats represented and long-term goals
* add stats api tests with/without authentication
* fix more fields to match data model
* fix more tests
* fix jest test
* remove TODO
* remove sockets
* use snake_case for api field names
* restore accidental removal + copy/paste error
* sourceKibana -> getKibanaInfoForStats
* skip usage test on legacy endpoint
* fix api tests
* more comment
* stop putting a field in that used to be omitted
* fix the internal type to ID the usage data for bulk uploader
* correct the kibana usage type value, which is shown as-is in the API
* more fixes for the constants identifying collector types + test against duplicates
* add a comment on a hack, and a whitespace fix
* [Monitoring/Telemetry] Move Usage service from Monitoring to Kibana core
* fix tests
* fix reporting integration
* roll back more diffs
* roll logger into bulk uploader to remove file duplication
* fix xpack usage api
* subclass constructor is not needed
* collectorSet has factory methods for collector object creation
* fix reporting usage jest test
* Separate bulk upload behavior from CollectorSet
- takes out a lot of behavior from CollectorSet and moves it to a class called BulkUploader
- simplifies kibana monitoring init by taking out the indirection that startCollectorSet / createCollectorSet had
- removes start() method from CollectorSet and calls the collector objects' init() functions from CollectorSet.register()
- removes cleanup method from collectorSet since that was doing work for bulk uploading
* remove cleanup and fetchAfterInit methods
* test for bulk_uploader class
* improve test for collector_set
* fix reporting
* expose collectorSet if there actually is a collectorSet
* comment for enclosed function
* make collectorSet creation/expose unconditional, bulkUploader more conditional
* fix collector_set tests
* lifecycle events
* stab at collectorSet error logging from the API call
* clean up comments
* clean up comments
* fix BulkUploader mocha test
* check kibanaCollectionEnabled config before registering bulk upload and the plugin status listeners
* no singleton timer object
* just log a warning if bulk uploader start called twice
* normal quotes
* check if bulk is enabled inside of the _fetchAndUpload method
* log for stopping bulk stats
* call bulkUploader.start with the collectorSet object
* call bulkUploader.start with the collectorSet object
* roll back change for module scoped variable
* oops I broke init
* init and logging: if / elseif / elseif
* remove unnecessary check/log
* help log
* remove redundant, use data.filter.map
* use xpackInfo.onLicenseInfoChange not xpackMainPlugin.status.on('green')
* help logging
* fix unit test
* remove handler that stops upload when connection is lost
* [Monitoring] Add a yellow status phase in the startup lifecycle
* comments
* more comments
* more comment
* undo register => registerType function name change
