Allow plugin to deploy to sites secured with Atlassian ID

[Min'an Tan]

Atlassian ID changes the login semantics for JIRA/Confluence/etc. instances. Initialising a new login session using HTTP Basic authentication no longer seems to work.

We need to work out how to authenticate against Atlassian ID as more and more instances within Atlassian are now using it.

See https://extranet.atlassian.com/jira/browse/BUILDENG-3701?focusedCommentId=408023&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-408023 for more details

[Joe Clark]

I did some investigation on BUILDENG-3701 (see my comment). The suggestion of pre-authenticating every request during the plugin upload won't always work. We need a better solution.

I've updated the issue title and description to reflect this.

[Min'an Tan]

There's more than initially thought here. See https://extranet.atlassian.com/jira/browse/BUILDENG-3701?focusedCommentId=412178&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-412178 onwards.

[Min'an Tan]

Attached interim patch here for posterity. Thanks for looking at this so quickly :)

[Joe Clark]

OK, I think we've got this licked now.

Raised https://extranet.atlassian.com/jira/browse/BUILDENG-3761 to get the patched add-on installed.