add missing Monolog handler type in XML config
bug #4147 [Cookbook][Logging] add missing Monolog handler type in XML config (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
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[Cookbook][Logging] add missing Monolog handler type in XML config

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets |

Omitting the type of a handler leads to an error:

> Symfony\Component\Config\Definition\Exception\InvalidConfigurationException: The child node "type" at path "monolog.handlers.swift" must be configured.

Commits
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dc33b0c add missing Monolog handler type in XML config
Added hint about attaching the expression constraint to a form field
feature #4086 [Reference][Constraints] Added hint about attaching the expression constraint to a form field (peterrehm)

This PR was submitted for the master branch but it was merged into the 2.4 branch instead (closes #4086).

Discussion
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[Reference][Constraints] Added hint about attaching the expression constraint to a form field

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | 2.4
| Fixed tickets | -

As per my discussion with @webmozart a while ago on twitter https://twitter.com/peterrehm/status/434350363940904960 I am now providing the hint about the possibility to add a expression constraint to a form field.

Commits
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3023dc3 Added hint about attaching the expression constraint to a form field
Merge branch '2.3' into 2.4

* 2.3:
  add missing Monolog handler type in XML config
Merge branch '2.4' into 2.5

* 2.4:
  Added hint about attaching the expression constraint to a form field
  add missing Monolog handler type in XML config