* refactor: move targetGroup struct and CheckOverflow() to their own package
* refactor: move auth and security related structs to a utility package, fix import error in utility package
* refactor: Azure SD, remove SD struct from config
* refactor: DNS SD, remove SD struct from config into dns package
* refactor: ec2 SD, move SD struct from config into the ec2 package
* refactor: file SD, move SD struct from config to file discovery package
* refactor: gce, move SD struct from config to gce discovery package
* refactor: move HTTPClientConfig and URL into util/config, fix import error in httputil
* refactor: consul, move SD struct from config into consul discovery package
* refactor: marathon, move SD struct from config into marathon discovery package
* refactor: triton, move SD struct from config to triton discovery package, fix test
* refactor: zookeeper, move SD structs from config to zookeeper discovery package
* refactor: openstack, remove SD struct from config, move into openstack discovery package
* refactor: kubernetes, move SD struct from config into kubernetes discovery package
* refactor: notifier, use targetgroup package instead of config
* refactor: tests for file, marathon, triton SD - use targetgroup package instead of config.TargetGroup
* refactor: retrieval, use targetgroup package instead of config.TargetGroup
* refactor: storage, use config util package
* refactor: discovery manager, use targetgroup package instead of config.TargetGroup
* refactor: use HTTPClient and TLS config from configUtil instead of config
* refactor: tests, use targetgroup package instead of config.TargetGroup
* refactor: fix tagetgroup.Group pointers that were removed by mistake
* refactor: openstack, kubernetes: drop prefixes
* refactor: remove import aliases forced due to vscode bug
* refactor: move main SD struct out of config into discovery/config
* refactor: rename configUtil to config_util
* refactor: rename yamlUtil to yaml_config
* refactor: kubernetes, remove prefixes
* refactor: move the TargetGroup package to discovery/
* refactor: fix order of imports
remove some select state that is most likely obsoleete and hoepfully doesn't braje anything :)
merge targets will sort by Discoverer name so we can have consistent tests for the maps.
* Adds a test covering the case where a target providers sends updated versions of the same target groups and the system should reconcile to the latest version of each of the target groups
* Refactors how input data is represented in the tests. It used to be literal declarations of necessary structs, now it is parsing yaml. Yaml declarations are half as long as the former. And these can be put in a fixture file
* Adds a tiny bit of refactoring on test timeouts
* flaky test caused by invalid fsnotify updates before the test files are written to disk causing the fd service to send empty `group[]` struct
* `close(filesReady)` needs to be before the file closing so that fsnotify triggers a new loop of the discovery service.
* nits
* use filepath.Join for the path url to be cross platform
* stupid mistake revert
