Blender Git Loki

===Python API===
Two small bugfixes:
* Image.New() resets id.us to 0; it is set to 1 by new_image()
* allow ima.depth and ima.size getters to propagate their own error
messages (missing image was returning MemoryError)

Also, seems to me there's something funny going on with image id.us
accounting. In do_image_buttons(), id.us is set whenever an image is
accessed vi the datablock menu:

if(idtest!=id) {
G.sima->image= (Image *)idtest;
if(idtest->us==0) idtest->us= 1;
allqueue(REDRAWIMAGE, 0);
}

This is independent of whether a UV face is selected or not (and it also
seems that the number of UV faces linked to an image is not maintained
either).