docs: Mark 5.0.7 additions.

al_set_display_flag
ALLEGRO_FRAMELESS

(cherry picked from commit db8d3a0adabad8abf199b0c52b8fef7b03c71f19)
docs: Mark 5.0.8 additions.

ALLEGRO_ALIGN_INTEGER

(cherry picked from commit 96ac8ead3445efb2649302428aefbce55284e6e5)
docs: Mark 5.0.9 additions.

al_set_display_icons
al_init_native_dialog_addon
al_shutdown_native_dialog_addon

(cherry picked from commit c0f013602e920501eaa4aa2b13d5904281861626)
Prepare summary of changes for 5.0.9.

(cherry picked from commit cd00ef61b3cf674ee42d3819150ae770aa77b94c)
Bump version to 5.0.9.
Bump version to 5.0.10 (GIT).