[PHP-DOC] warn.experimental.func

[Keito Uchiyama]

I have two questions: who/what decides if a function is "experimental", 
and when do they become non-experimental? Also, does the tag apply to 
PECL extensions (e.g. ncurses) as well, given that it disclaims against 
changes in "future versions of PHP"?

Thanks!
Keito