and various cleaning in Altivec code. Altivec vectorization have been re-enabled
in CoreDeclaration
* added copy constructors in non empty functors because I observed weird behavior with
std::complex<>
* rework PacketMath and DummyPacketMath, make these actual template
specializations instead of just overriding by non-template inline
functions
* introduce ei_ploadt and ei_pstoret, make use of them in Map and Matrix
* remove Matrix::map() methods, use Map constructors instead.