Ensured that single triangles and tetrahaedrons give sensible results

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/geometry@144 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Moved delaunayn tests to testthat

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/geometry@145 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Moved parallel tests to testthat

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/geometry@146 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Moved comparison of tsearch and tsearchn to testthat

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/geometry@147 edb9625f-4e0d-4859-8d74-9fd3b1da38cb