#386 Font manager plugin in system module

[irmtfan]

Font manager is also needed.
Many xoops modules and function could use this font plugin.
eg: captcha, xoops editors, external editors, image watermark, ,,,
Recently there are some new conversations about adding "tcpdf" to the next xoops 2.6 as a new library.
see:
http://xoops.org/modules/newbb/viewtopic.php?post_id=347757

It should had the ability for adding different fonts for "Local" support.
I suggest to use a local folder for local fonts:
eg: language/LANG/fonts