examples/kruskal-example.cpp shadows variables

[nobody]

$g++ -Wshadow -Wall kruskal-example.cpp -lbgl-viz

generates a lot of shadow warnings, making it
impossible to use kruskal-example related code in a
program that is supposed to be shadow-free.

$g++ --version                                   
g++ (GCC) 3.3.3 (Debian 20040321)
Copyright (C) 2003 Free Software Foundation, Inc.
This is free software; see the source for copying
conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.

[Douglas Gregor]

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user_id=249098

Wow, that is a lot of warnings! There are too many fixes needed to do 
this for 1.32.0, but we'll get it fixed afterward.

[Douglas Gregor]

Logged In: YES 
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Fixed code to eliminate all shadow warnings for Boost 1.33.0.