Create an image.
FILE-OR-DATA is an image file name or image data.
Optional TYPE is a symbol describing the image type. If TYPE is omitted
or nil, try to determine the image type from its first few bytes
of image data. If that doesn't work, and FILE-OR-DATA is a file name,
use its file extension as image type.
Optional DATA-P non-nil means FILE-OR-DATA is a string containing image data.
Optional PROPS are additional image attributes to assign to the image,
like, e.g. `:mask MASK'.
Value is the image created, or nil if images of type TYPE are not supported.
Images should not be larger than specified by `max-image-size'.
Image file names that are not absolute are searched for in the
"images" sub-directory of `data-directory' and `x-bitmap-file-path' (in that order).