* libguile/uniform.h (scm_array_handle_uniform_element_bit_size): New
public accessor.
* libguile/uniform.c (scm_array_handle_uniform_element_size): Better
errors in non-byte-aligned arrays.
(scm_uniform_vector_element_type, scm_uniform_vector_element_size)
(scm_c_uniform_vector_ref, scm_c_uniform_vector_set_x):
(scm_uniform_vector_to_list): Don't require byte-aligned access.
* libguile/bytevectors.c (scm_uniform_array_to_bytevector):
* libguile/arrays.c (scm_from_contiguous_typed_array): Fix for
uniform arrays whose element size is not a multiple of the byte size.