Create sniff to ensure empty after { and before } in class/interface/trait

[aik099]

There is a Squiz.WhiteSpace.FunctionSpacing sniff, that checks, that:

• there 1 line before/after function declaration
• there is an empty line after last function declaration in a class (only since PHPCS 2.2.0, squizlabs/PHP_CodeSniffer@4bc2418)

I mistakenly assumed that check was made to ensure 1 empty line after class opening brace.

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Need to write sniff that will:

• ensure 1 empty line after { (basically line after line where { is placed should be empty)
• ensure 1 empty line before } (basically line before line where } is placed should be empty)