docs: introduce deprecation root pages

[profanis]

The reason for this change is the following:

Let's assume a developer works in a company where they decide to migrate to the version where the select decorator is deprecated. Although it's being deprecated they might need some time to convert their code. At the same time, they might need/want to read about the select decorator. If we completely remove the docs, it's harder for them to find the information they are looking for

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BundleMon (Integration Projects)

Unchanged files (2)

Status | Path | Size | Limits :------------: | ------------ | :------------: | :------------: :white_check_mark: | Main bundles(Gzip)
_{hello-world-ng17/dist-integration/main.(hash)
.js}
| 68.49KB | +1% :white_check_mark: | Main bundles(Gzip)
_{hello-world-ng16/dist-integration/main.(hash)
.js}
| 67.03KB | +1%

Total files change +9B +0.01%

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Current branch size history | Target branch size history

[profanis]

We need to update the docs references in the deprecation doc comments in the actual code too.

@markwhitfeld I am afraid I didn't get what needs to be fixed.

[arturovt]

I think Mark refers to this code:

[arturovt]

And for children too

[profanis]

We need to update the docs references in the deprecation doc comments in the actual code too.

I updated the doc references @markwhitfeld

[codeclimate[bot]]

Code Climate has analyzed commit 09418a48 and detected 0 issues on this pull request.

The test coverage on the diff in this pull request is 100.0% (50% is the threshold).

This pull request will bring the total coverage in the repository to 95.2% (0.0% change).

View more on Code Climate.