Fix PSR coding standards error
minor #3658 Fix PSR coding standards error (ifdattic)

This PR was merged into the 2.3 branch.

Discussion
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Fix PSR coding standards error

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | 2.3
| Fixed tickets |

Commits
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da2ee60 Fix PSR coding standards error
868de1e minor #3698 Dynamic form modification cookbook: Fix inclusion of code  (michaelperrin)
acf255d feature #3328 [WIP] Travis integration (WouterJ)
5d99d88 [#3697] Backporting 2.3-specific changes
1e8b0d4 Small fixes in code style
8093719 Dynamic form modification cookbook: Fix inclusion of code
37eb137 Update documentation
8dec729 sparse checkouts
b6f693e Added CMF
b1d9e62 Revert changes
6cad008 Updated travis config
c515613 Added .gitignore
85b1b02 Try to supress bundle doc warnings
f3cb8b1 Fixed submodules
71a2ff4 Added needed config files
d312683 Added sphinx files