Squashed commit of the following:

    apps/examples/lvgldemo:  Fix up some include paths
    apps/examples/lvgldemo:  The last final now conforms to the NuttX coding style.
    apps/graphics/littlevgl:  Two more files are closer to the NuttX coding style.
    apps/graphics/littlevgl:  Two more files are closer to the NuttX coding style.
    apps/examples/lvgldemo:  Three more files are closer to the NuttX coding style.
    apps/examples/lvgldemo:  Two more files are closer to the NuttX coding style.
    apps/examples/lvgldemo:  Two more files are closer to the NuttX coding style.
    Add include/graphics/.gitignore
    apps/include/graphics:  Remove lvgl.h.  graphics/littlevgl/Makefile now copies the file into position.
    apps/graphics/littlevgl:  Add .gitignore file
    apps/graphics/littlevgl:  Most of these files follow the coding style now.
    apps/graphics/littlevgl:  This gets a couple of files closer to the NuttX coding style.
    apps/examples/lvgldemo:  Add lvgldemo example
    apps/graphics/littlevgl:  Add littlevgl library