Fixes #18438 - control notifications polling

fixes #14178 - Introduce patternfly toast notifications

fixes #14178 - introduce react patternfly toasts

fixes #19192 - adds mark all as read notification action

This implements missing feature from patternfly ( see http://www.patternfly.org/pattern-library/communication/notification-drawer/#/code/angular)

Fixes #18957,#18193,#18678,#18853 - notifications redux

Refactored notifications to work with redux, fixed
several UI related bugs, added tests.
flux is now unused, this is based on @gailsteiger's
previous work.

Fixes #18888 - refactor powerStatus

Fixes #18591 - powerStatus in redux

refs #18464 - rename *.spec.js to *.test.js

fixes #18464 - Add Redux to statistics page

This is a first step to replacing Flux with Redux