18.3.0

• bn::sprite_text_generator::generate_top_left and bn::sprite_text_generator::generate_top_left_optional added.
• bn::sprite_text_generator allows to setup the mosaic, the blending, the visibility and the camera of the output sprites.
• bn::sprite_builder::release_affine_mat, bn::sprite_builder::release_camera, bn::regular_bg_builder::release_camera and bn::affine_bg_builder::release_camera fixed.
• bn::sprite_builder, bn::regular_bg_builder and bn::affine_bg_builder documentation improved.