(CTH-356) Add loglevel option; ignore HorseWhisperer's vlevel
(CTH-356) Add loglevel option; ignore HorseWhisperer's vlevel

Using the new loglevel option for setting the logging level. Ignoring
the vlevel option provided by HorseWhisperer via -v, -vv, -vvv, etc.

puppetlabs/pxp-agent,puppetlabs/pxp-agent,puppetlabs/pxp-agent