[meta] Statements

[Hywan]

Address #11.

Specification

https://github.com/php/php-langspec/blob/master/spec/19-grammar.md#statements

Progression

• General,
• Compound statements,
• Labeled statements,
• Expression statements,
• Iteration statements,
• Jump statements,
• The try statement,
• The declare statement,
• Functions,
• Classes,
• Interfaces,
• Traits,
• Namespaces.