Evas: Changing the font engine to work with Eina_Unicode instead of utf8.

Evas: Changing the font engine to work with Eina_Unicode instead of utf8.
Changing textblock and text objects to work with Eina_Unicode instead of utf8 (internally, API remains intact).
Started relying on new fribidi 0.19.2 instead of the old fribidi.
A lot of fixes to the font engine.
Renaming of evas_common_font_utf8_* to evas_common_encoding_utf8_*
This relies on new Eina changes and types: Eina_Unicode, Eina_UStrbuf and Eina_UStringshare.

git-svn-id: svn+ssh://svn.enlightenment.org/var/svn/e/trunk/evas@50595 7cbeb6ba-43b4-40fd-8cce-4c39aea84d33