IsisIO: Become compliant with ISIS 3.4.3

The dropped the 'get' prefix on some of their methods. They switched
over to QString in more places.
pprc: Have sub images rendered in parallel with sub_tile_size

Sub_tile_size and sub_theads are still important to make sure that
rendering the low res images doesn't allocate a ton of
GB. Cache_tile_aware_render stop us from notice we had a
problem. However if the sub_scale ration is greater than five ... or
if there just existed a really weird homography, it was possible that
stereo_pprc would try to allocate many GB of ram. This brings down the
system because it is swapping memory so hard.
Core: Make blob consolidation step threaded

It takes a long 5 minutes on larger imagery.
core: Fix blob x shifting on invalid value

The code was sometimes using front() on an empty list. This is
undefined behavior.

 LocalWords:  unstage src config
Core: Use a more exhaustive intersect

Instead of just intersecting the bounding bboxes, intersect the actual
shapes.
all: Drop shared_dynamic_cast for dynamic_pointer_cast

Boost 1.53 dropped shared_dynamic_cast. Dynamic_Pointer_Cast is the
more general function and already exists in the older boosts.
stereo_corr: Cleanup debug info
stereo_mpi: Try to create the soft links at each step
stereo_corr: Make local-homography a command line option