Review and add all PHP 7.0 features

[rosswintle]

https://www.php.net/manual/en/migration70.new-features.php

• Scalar type declarations
• Return type declarations
• Null coalescing operator
• Spaceship operator
• Constant arrays using define()
• Anonymous classes
• Unicode codepoint escape syntax
• Closure::call()
• Filtered unserialize()
• IntlChar
• Expectations
• Group use declarations
• Generator Return Expressions
• Generator delegation
• Integer division with intdiv()
• Session options
• preg_replace_callback_array()
• CSPRNG Functions
• list() can always unpack objects implementing ArrayAccess
• Class member access on cloning

https://www.php.net/manual/en/migration70.deprecated.php

• PHP 4 style constructors
• Static calls to non-static methods
• password_hash() salt option
• capture_session_meta SSL context option
• ldap_sort()
• gc_mem_caches()
• get_resources()
• posix_setrlimit()
• ReflectionParameter::getType()
• ReflectionParameter::hasType()
• ReflectionFunctionAbstract::getReturnType()
• ReflectionFunctionAbstract::hasReturnType()
• ZipArchive::setCompressionIndex()
• ZipArchive::setCompressionName()
• inflate_add()
• deflate_add()
• inflate_init()
• deflate_init()

https://www.php.net/manual/en/migration70.classes.php

• IntlChar
• ReflectionGenerator
• ReflectionType
• SessionUpdateTimestampHandlerInterface
• Throwable
• Error
• TypeError
• ParseError
• AssertionError
• ArithmeticError
• DivisionByZeroError

https://www.php.net/manual/en/migration70.new-functions.php

• random_bytes()
• random_int()
• error_clear_last()
• Generator::getReturn()
• gmp_random_seed()

https://www.php.net/manual/en/migration70.constants.php

PHP_INT_MIN
IMG_WEBP
JSON_ERROR_INVALID_PROPERTY_NAME
JSON_ERROR_UTF16