Download convenience build option does not work

[skurnevich]

Zowe Server Install Wizard doesn't seem to work well when selecting download convenience build; progress is missing and hangs.

Downloading does not actually happens, it immediately completes with empty zowe.pax and so fails to unpax and parse
Also it takes v2+ as a latest version

[1000TurquoisePogs]

@struga0258 to test this at Rocket, see if this is environmental or a regression overall.

[struga0258]

This is a regression, I was able to confirm this bug. The download never seems to happen, and zen just continues with upload and unpax but eventually fails since there is no pax.

[1000TurquoisePogs]

This is likely a result of the artifactory moving to a redirect-based download method.
The URLS we get return with HTTP 302 redirects recently.
And nodejs' https request library does not automatically handle redirects, so an enhancement must be made to detect the redirect and respond by issuing a second request to the redirect destination.

[struga0258]

This bug should be fixed by #271