Remove the column-cache from the code generator. The column-cache has been

Remove the column-cache from the code generator.  The column-cache has been
a persistent source of bugs for years and with recent improvements
in the performance of OP_Column, it no longer provides a benefit.  After
the column cache is removed, the binary is almost 2KB smaller and the
speed-check.sh performance test is over 3 million cycles faster.

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