eina_unicode: fix header inclusion.

eina_unicode: fix header inclusion.

library files should ALWAYS include config.h, they should not include
Eina.h using "<Eina.h>" to avoid messing with system's version.

Last but definitely not least: include safety checks BEFORE your local
header, otherwise the macros EINA_ARG_NONNULL() will remove every
check for null pointers! eina_safety_checks.h redefines it to empty so
compiler does not optimize these things.

git-svn-id: svn+ssh://svn.enlightenment.org/var/svn/e/trunk/eina@67392 7cbeb6ba-43b4-40fd-8cce-4c39aea84d33