* Refactor: moves all the newVariables part to features/variables directory

* Feature: adds datasource type

* Tests: adds reducer tests

* Tests: covers data source actions with tests

* Chore: reduces strict null errors

* boilerplate that will be replaced by real code.

* added old editor template.

* added initial version of ad hoc editor.

* added working (apart from add) version of the editor.

* Added placeholder for picker.

* Have a working UI. Need to connect it so we refresh the variables on changes.

* variable should be updated now.

* removed console.log

* made the url work.

* cleaned up the adapter.

* added possiblity to create filter directly from table.

* moved infotext from general reducer to extended value of adhoc.

* fixed strict null errors.

* fixed strict null errors.

* fixed issue where remove was displayed before being added.

* fixed issue with fragment key.

* changed so template_src is using the redux variables.

* minor refactorings.

* moved adhoc picker to adhoc variable.

* adding tests for reducer and fixed bug.

* added tests or urlparser.

* added tests for ad hoc actions.

* added more tests.

* added more tests.

* fixed strict null error.

* fixed copy n pase error.

* added utilit for getting new variable index.

* removed console.log

* added location to reducerTester type and created a module type for it.

* changed so we only have one builder pattern.

* fixed tests to use static expected values.

* fixed strict errors.

* fixed more strict errors.

Co-authored-by: Hugo Häggmark <hugo.haggmark@grafana.com>