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

Eigen/src/Cholesky/LDLT.h

@@ -88,7 +88,7 @@ template<typename MatrixType> class LDLT
 
     /** \returns a vector of integers, whose size is the number of rows of the matrix being decomposed,
       * representing the P permutation i.e. the permutation of the rows. For its precise meaning,
-      * see the examples given in the documentation of class LU.
+      * see the examples given in the documentation of class FullPivLU.
       */
     inline const IntColVectorType& permutationP() const
     {