Convert libgvfscommon to a private shared library
Convert libgvfscommon to a private shared library

Convert libgvfscommon to a private shared library since it is not used
by anything outside of the libdir.  Also, don't version it.

https://bugzilla.gnome.org/show_bug.cgi?id=561187

gicmo/gvfs,gicmo/gvfs,gicmo/gvfs,gicmo/gvfs