big huge changes, so i dont remember everything.

* renaming, e.g. LU ---> FullPivLU
* split tests framework: more robust, e.g. dont generate empty tests if a number is skipped
* make all remaining tests use that splitting, as needed.
* Fix 4x4 inversion (see stable branch)
* Transform::inverse() and geo_transform test : adapt to new inverse() API, it was also trying to instantiate inverse() for 3x4 matrices.
* CMakeLists: more robust regexp to parse the version number
* misc fixes in unit tests

unsupported/Eigen/src/MatrixFunctions/MatrixExponential.h

@@ -192,7 +192,7 @@ MatrixExponential<MatrixType>::MatrixExponential(const MatrixType &M, MatrixType
   computeUV(RealScalar());
   m_tmp1 = m_U + m_V;	// numerator of Pade approximant
   m_tmp2 = -m_U + m_V;	// denominator of Pade approximant
-  m_tmp2.partialLu().solve(m_tmp1, result);
+  *result = m_tmp2.partialPivLu().solve(m_tmp1);
   for (int i=0; i<m_squarings; i++)
     *result *= *result;		// undo scaling by repeated squaring
 }