minor #2830 Minor fix in the design of exception pages (javiereguiluz)
minor #2830 Minor fix in the design of exception pages (javiereguiluz)

This PR was merged into the 2.0.x-dev branch.

Discussion
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Minor fix in the design of exception pages

Very minor tweak. Before:

![image](https://user-images.githubusercontent.com/73419/60766825-6a9e7000-a0af-11e9-8f0a-1e408aa26364.png)

After:

![image](https://user-images.githubusercontent.com/73419/60766828-6d00ca00-a0af-11e9-97e1-a56304907102.png)

We now correctly remove the empty header/footer content.

Commits
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c7d66d3f Minor fix in the design of exception pages

javiereguiluz/EasyAdminBundle,OskarStark/EasyAdminBundle,OskarStark/EasyAdminBundle,OskarStark/EasyAdminBundle,javiereguiluz/EasyAdminBundle