answer some questions and clarify the best chapter imo from the symfony documentation
address comments from @WouterJ
bug #3423 [Session Configuration] add clarifying notes on session save handler proxies (cordoval)

This PR was merged into the 2.3 branch.

Discussion
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[Session Configuration] add clarifying notes on session save handler proxies

| Q             | A                   |
| ---           | ---                 |
| Doc fix?      | yes                 |
| New docs?     | no                  |
| Applies to    | 2.3+                |
| Fixed tickets | #2889               |
| License       | CC-ASA 3.0 Unported |

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Commits
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771b862 address comments from @WouterJ
2888d00 answer some questions and clarify the best chapter imo from the symfony documentation