added missing data sets for regression tests

  adding additiona regression tests from vis12 branch

  Create branch for adding OpenCL to vis12 branch.  Based on r2401 of the vis12 branch.

  Fix missing promotion cases

  converting to use "image" instead of "load" for image nrrd loading

  Update regression tests for new output mechanism and to use --exec flag

  Create a branch to implement things that we need for the Vis 2012 paper

  merging changes from pure-cfg

  Added support for hest-based command-line arguments to trunk.  Also switched
  output filename to prog.txt (from mip.txt)

  Adding support for assignment operators to the trunk.

changed output image size from 200 to 201 to avoid sensitivity to FP error on inside() test, and made assess.sh slightly more tolerant of FP error

test more lenient WRT FP round-off

test more lenient WRT FP round-off

making test more permissive of rounding errors

a simple volume-rendering test

have tweaked data

some comments

making slow tests run faster

another test

new tests

more tests

basic test of 3D convolution

  Scripting support for regression tests

  Move regression tests into the tests subdirectory so that we can more easily
  script the testing process.