adding allow-none and out caller-allocate introspection metadata to pango_layout_set_markup_with_accel. Correct some documentation typos.
adding allow-none and out caller-allocate introspection metadata to pango_layout_set_markup_with_accel. Correct some documentation typos.

Distrotech/pango,danny-ku/pango,danny-ku/pango,Distrotech/pango,kari-lentz/alpha-pango,Distrotech/pango,kari-lentz/alpha-pango,kari-lentz/alpha-pango,kari-lentz/alpha-pango,danny-ku/pango