add skeleton for test_dense
results_io: remove unused load_imgs param
factor out PASCAL image load params/snippet.

there are more dupes left but they differ more in param defaults (still no good way to handle that ...) or usage and seem harder to factor out.
use models_dir instead of home_dir to find alexnet
configure test_dense defaults to use nin_imagenet_nopad model
geom_prim: add pt_T::max_eq()
results_io: add a typedef
caffeif: add questionable static boolean to prevent double-init of caffe.
geom_prim: fill in some more pt_T min/max/min_eq/max_eq funcs
img_io: condense img_copy_to{,_clip} into just img_copy_to_clip(), and add (untested/unused) src_pt and max_copy_sz params
display_pil: add rand_winds option for testing image_copy_to_clip size and src_pt options
rand_util: header for factoring out boost::random-using code
use rand_util.H
display_pil: use rand_util.H; add dest_pt randomization
test_dense: use rand_util.H; a bit more progress.
conv_util: in dump_ios(), distinguish DATA DISCARDED and IMPLICIT PAD cases when sz != used_sz.

the IMPLICIT PAD case was not possible before the pooling was tweaked
to match the caffe semantics of allowing implicit padding for the +
most x/y padding output.
img_io: add make_p_img_t(sz) func.
test_dense: a bit more progress. actually attempt to run window / full image through caffe.