Core: Change hole filling to perform filtering on demand

This should ideally use less memory.
stereo_mpi: Make sure we mosaic before leaving rfne step

Otherwise we can't just pick back up with stereo_fltr
dg_mosaic: Support for single entry TLC
Core: Remove some unneeded allocations
Orthorasterer : speed up by accessing input less

The prerasterize step should now make only 1 crop into the input
imagery instead of several. This greatly speeds up the process as most
threads are just waiting to get a crop of the input.
point2dem: Rasterize all triangles

Lets rasterize even the triangles that will clip on the image.
time_trials: Show real, user, and system
OrthoRaster: Fix quadtree progress bar
Orthorasterizer: Code clean up

Fix the tabing and bring back in the expand 1 that I dropped
earlier. It is need because we are getting floating point intersection
wrong somewhere.
Core.h: Remove specialized hears from Core.h

The existance of Core.h seems like a bad idea. I was just copying
VW. Misuse of this file just make compilation times longer.
point2dem: Remove block_cache for improvement

Block cache is no longer needed now that OrthoRasterizer has a better
access pattern. We actually do better and have more cache if we don't
use block_cache.
dg_mosaic: Add incorrect image placement check

See if we are trying to insert more than one image to a line location.