[#3276] Trying to further clarify the session storage directory details
[#3404] Adding a few comments, per @WouterJ
minor #3404 [#3276] Trying to further clarify the session storage directory details (weaverryan)

This PR was merged into the 2.3 branch.

Discussion
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[#3276] Trying to further clarify the session storage directory details

Hi guys!

This continues after #3342. Basically, it's confusing the symfony/symfony has a different default than the Symfony SE. However, I agree with Wouter that most framework readers are probably SE users. My strategy is simply to show people which configuration causes which situation.

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all (or 2.3+)
| Fixed tickets | #3276

Thanks!

Commits
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adc57be [#3404] Adding a few comments, per @WouterJ
f094237 [#3276] Trying to further clarify the session storage directory details