Refactored EG(active_symbol_table) to be zend_array* instead of HashTable*

Fixed passing arguments by reference from internal functions

Review ended

Revert "An demo(for review) to show how to fix the problem(symbol table resize)"

This reverts commit 60c354510b6731ec8348af9c5e230a4859c7c383.

An demo(for review) to show how to fix the problem(symbol table resize)

Revert "An demo(for review) to show how to fix the problem we meet"

This reverts commit 4aeae157062f69deb36e16f13ff0ddff62fd487c.

An demo(for review) to show how to fix the problem we meet

Fixed memleak while sending IS_REFERENCE

Fixed refcounting

Internal functions may return (e.g. on wrong arguments) keeping the original return_value. So we have to initialize return_value as IS_NULL.

Fixed passing reference by value in call_user_func()

Fixed support for undefined constants in RECV_INIT

Fixed by reference parameter passing from internal functions

Handle interned strings as non-refcounted scalars

Fixied calling object closures from internal functions

Fixed constant expressions in array indeces handling

Various fixes related to read_property(), read_dimension() and iterators refactoring

Fixed refcounting

Fixed memory leak

Changes zend_is_callable() to use zend_string* instead of char*

Fixed NULL pointer dereference

Fixed create_function()

More constant related fixes

fixed support for constant expressions

Fixed invalid write in vsprintf tests

Fixed zend_rebuild_symbol_table() using IS_INDIRECT