Check all arguments for validity when calling the .preload method again

[Maikenov]

check all arguments for validity when calling the .preload() method again

mode should only accept values "identity, shift_and_scale","shift and scale, "to_cube", "to cube"

the rest of the arguments (scale, ns_padding, ps_padding, keep_in_memory) should only take on the value type specified in the documentation.
An error should be thrown if the argument types do not match.