mbstring.func_overload is going to be depreciated

Hi all,

mbstring has php.ini mbstring.func_overload switch that overloads
single byte string functions by mbstring's multibyte enabled functions.

This switch was intended to use with application that works only with
single byte chars. However, frameworks like CakePHP, etc have code
that deal with switch. This was never intended.

I'll update doc to tell users this feature will be depreciated in future
PHP versions. I think removing this switch PHP 7 or later is good.

Any comments?

Regards,

--
Yasuo Ohgaki
yohgaki@ohgaki.net