Add version macros
Added macros:
- SECRET_VERSION_MAJOR
- SECRET_VERSION_MINOR
- SECRET_VERSION_MICRO
- SECRET_CHECK_VERSION
These macros are widely defined in GLib based library. For example, GLib, GTK, poppler GLib and so on define them.
These macros are useful to detect libsecret version on build time and from GObject Introspection based bindings.
Edited by Sutou Kouhei