Documented deprecation of the apache router.
feature #3446 [WCM] Documented deprecation of the apache router. (jakzal)

This PR was merged into the master branch.

Discussion
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[WCM] Documented deprecation of the apache router.

| Q             | A
| ------------- | ---
| Doc fix?      | no
| New docs?     | no
| Applies to    | 2.5+
| Fixed tickets | -

Commits
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fdf4891 Documented deprecation of the apache router.