Support for older system that don't come with libmount or have
an older libmount. This is a backport from Eeze 1.7 tree. There
is no code change there.
Changes also in this commit:
* fix missing EAPI in symbols used by modules
* removed old libudev and libmount support as agreed by discomfitor/zmike
* replaced __UNUSED__ with EINA_UNUSED
* fixed docs hierarchy
SVN revision: 82100