Added information about float choice lists
feature #4241 [Form] Added information about float choice lists (peterrehm)

This PR was submitted for the 2.5 branch but it was merged into the 2.3 branch instead (closes #4241).

Discussion
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[Form] Added information about float choice lists

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

Added an information about the possibility to have a choice list with float values.

Relates to symfony/symfony#11849

Commits
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81e3728 Added information about float choice lists