Support Proxy Basic Authentication

[andrewm-aero]

Dependencies

N/A

Feature Request

The original install-plugins.sh, as well as Jenkins itself supports basic authentication for HTTP(s) proxies, however, the README states that something like CNTLM is required to achieve the same functionality. The JVM properties http(s).proxy[User/Password] are in common enough use, as are authenticated corporate proxies, that that they ought to be supported. Deprecating install-plugins.sh without porting this existing functionality would break many setups when install-plugins.sh is eventually removed.

[oleg-nenashev]

I am breaking down options in #237 . After it is completed, it should be easier to introduce new options like proxy auth

[amfleurke]

I think this issue can be closed. The plugin-installation-manager tool supports proxy via default java options (-Dhttps.proxyHost etc)
See also project readme.md. Works for me.