Make CloneNode obsolete

[robertwb]

As we start making changes affecting the value of node.result() during post-analysis transforms, CloneNode is a potential problem. Many of them can now be replaced by TempBlockNode (preferred from transforms) or code.funcstate.allocate_temp (preferred if the temp is really only needed within the code generation functions of the node).

This should be within the realm of possibility:

dagss:~/cython/tempblock$ grep CloneNode -r Cython/Compiler/*Nodes.py |grep -v '#' | grep -v '^class' | wc -l
12

Migrated from http://trac.cython.org/ticket/81

[robertwb]

@dagss changed summary from

Deprecate CloneNode

to

Make CloneNode obsolete
commented