Switch from ZEND_ACC_DYNAMIC to ZEND_ACC_ALLOW_STATIC and disallow calling

Switch from ZEND_ACC_DYNAMIC to ZEND_ACC_ALLOW_STATIC and disallow calling
internal non-static methods statically.
# As discussed with Zeev:
# - For BC standard userspace methods allow this with an E_STRICT message.
# - If you want to implement an internal method taht can be called both
#   statically and non-statically then use flag ZEND_ACC_ALLOW_STATIC.
# - Magic user space methods __*() cannot and __construct, __destruct,
# __clone can never be called statically.