forms/types/collection
resolves #260
指摘いただいた箇所を修正いたしました。
Merge pull request #259 from yositani2002/reference/forms/types/collection.rst

[翻訳]reference/forms/types/collection.rst
二重バッククオートでtrueを囲みました。
Merge pull request #261 from yositani2002/reference/forms/types/options/error_bubbling.rst.inc

[翻訳]reference/forms/types/options/error_bubbling.rst.inc
Merge branch 'master' of https://github.com/symfony-japan/symfony-docs-ja into reference/forms/types/integer.rst
とりあえず保存。