MCOL-1786 Handle "true" keyword for numeric data types in cpimport

[tntnatbry]

This also adds support for MCOL-266 in cpimport.

[drrtuy]

Greetings and many thanks for this contribution. The change looks good so we will proceed with checks.
Could you again confirm that you give this code under BSD license as David Thompson suggested.

[tntnatbry]

Hi @drrtuy, I am submitting this patch under the BSD-new license.

[LinuxJedi]

Many thanks for your contribution. Looks good to me but I want to hold off for a little bit as we are about to close the merge window. We will aim to get this into version 1.2.1.