Documented html5 option
Typo fix
Yet another typo fix
feature #4487 Documented html5 option (WouterJ)

This PR was merged into the 2.6 branch.

Discussion
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Documented html5 option

| Q   | A
| --- | ---
| Doc fix? | no
| New docs? | yes (https://github.com/symfony/symfony/pull/8291, https://github.com/symfony/symfony/pull/11994)
| Applies to | 2.6+
| Fixed tickets | https://github.com/symfony/symfony-docs/issues/4262

Commits
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d08925e Yet another typo fix
238beef Typo fix
22069f4 Documented html5 option