CPPLapack Code

*bug fix on dsymatrix::set function. Thanks, Hui Li!!
*change the return object type of zero,initialize,and set functions
to enable quick initialization like ...
const dgematrix A(dgematrix(3,3).zero().set(1,1,x));

*change the spec of stretch function of dgsmatrix and dssmatrix

*change some CPPL_DEBUG lines to CPPL_VERBOSE lines.

bug fix for stretch of dgsmatrix and dssmatrix

*bug fix for dssmatrix

*halfway development of dssmatrix

*a few bug fix for copy constructor of smart temporary classes
*some modification of dssmatrix (not yet included in cpplapack.h)

dssmatrix was renamed to dgsmatrix.
(zgsmatrix is under construction.)

modification to get rid of forbidden codes
*added nullify function for all smart-temporary classes
*put nullify() at the end of shallow_copy functions and shallow copy constructors
*modified destroy function to assign NULL to all pointers

added dssmatrix::stretch function