azul3d_stencil: slightly better documentation.
azul3d_stencil: cleanup creation of the background image.
azul3d_texcoords: fix typo.
azul3d_stencil: only update camera when framebuffer is resized.
azul3d_stencil: clarify relative movement more
azul3d_stencil: document shapeTexCoords
azul3d_stencil: properly cache textures again after azul3d/gfx#75 was reverted.