#618 TIP#363 - vector math, partial reference implementation

[Karl C. Hansen]

Implements vector-vector, vector-scalar, and scalar-vector add/sub/mul/div in expr.

Very minor impact on core execution. Two files touched in generic:

tclInt.h -- added a couple of macros to help processing lists of numbers

tclExecute.c -- added vector-vector and vector-scalar handling per above

Compiles & runs with 8.6b1.

VTest.tcl exercises the mods. Printf's show where the code is running....

Handles stuff like:

set V [list 5 4 3 2 1]
set W [list 1 2 3 4 5]

expr {$V + $W}

set X 10

expr {$V * $X}

expr {$X / $V}

[Karl C. Hansen]

Modified from 8.6b1

[Karl C. Hansen]

Modified from 8.6b1

[Karl C. Hansen]

Test script for vector-vector, vector-scalar, and scalar-vector ops