Update plotting routines.
Update the Matlab plotting routines.
Note that ASCII must be read backwards in latitude
to make the first point into the south-west corner.
Found/fixed a problem with ascii_arc_bathy class.
  - Depths points must be flipped upside down to
    match USML conventions.
Changed sand attenuation from 0.8 to 0.01
  - per e-mail from Megan Ballard
Write all outputs to florida straits source directory.
Fixed ascii_arc_bathy backwards the last time.
Now the receiver depths n run1a_proploss are correct.
Allow for manual forward and reverse in wavefront plot.
Merge branch 'florida_straits' of /media/sf_usml-git into florida_straits
Making progress on the wavefront plot.
Direct and in-shore paths clearly visible.
But there appear to be discontinuities in the ray paths.
This gets worse when the starting point is placed
directly on the bottom.
Checking this in as "progress so far".
Just some Matlab test routine updates.
Draft of solution to Issue #18 Ray path discontinuity
- The near-miss logic in reflection_model::bottom_reflection()
  was not correct.
- Small errors in the surface normal have a large effect when
  the ray path is nearly parallel to the ocean floor.
- If the reflection does not point the ray back-into the water column,
  the next time step will include an erroneous reflection in which
  both the current and next location are below the bottom.
Still having a problem with reflection
when ray is nearly parallel with bottom.
Getting ready to try a different approach.
Save this version before heading in a new direction.
Getting a little bit better.
- Changed reflection model to have minimum grazing angle
  of about 0.23 degree.
- Replaced ascii_profile_factory with ascii_profile and integrated
  into Florida Straights test.

But now, there is a problem in wave_front::update().
- Calculation of ndir_gradient.theta() sometimes returns garbage.
- Putting in a debugging cout makes the problem go away.
- Sounds like a problem with the stack.
Add ascii_profile class to read SVP from text file.
Grab the latest version of Matlab scripts.
Turn off debugging print statements.
May have found the reflection problems.

1) The "too shallow" calculation was not normalizing the
   theta and phi components of the normal correctly.
   And this allowed them to be much greater than 1.
   Which led to crazy jumps.

2) The boundary_grid model has a sqrt() in the calculation
   of the rho component of the normal.  If the gradients
   are very large, the sum of the squares of the theta
   and phi components were slightly greater than 1.
   This leads to a rho value of NaN, and then everything
   turns bad.

Save this interim solution before we try to clean up the debugging
print statements.
Making some progress.
- Start with source 5 m above the bottom.
- Ensure that bathymetry covers entire ensonsified area.
- A few rays are still having discontinuities after passing the target.
- Eigenrays calculated by not yet analyzed.
Refine some of the data plotting routines.
Increase launch AZ angles to +20 degs.
Started development on paper and powerpoint.
Having trouble getting any eigenrays for targets beyond 10 km.
And the short range targets don't have an upslope component.