[feature] Switch to the new dashboard

[joewiz]

Description:

• This PR replaces the old dashboard with the new dashboard for the purpose of populating the autodeploy directory during a normal and installer builds.
• This PR assumes the URL for accessing the dashboard app has not changed, as required by Restore app name to be “dashboard” so links don’t break existdb-dashboard#13 and fixed by Adopt original dashboard app URL existdb-dashboard#14 (still awaiting merge at the moment).

Many developers have been using and testing the new dashboard and, as discussed in the January 7, 2018 community call, recommend that the new dashboard be included in the next 5.0.0-RC. (There are no current plans to backport this to the 4.x.x series.)

Reference:

• January 7, 2018 community call
• Numerous completed action items relating to Dashboard

Type of tests:

• I tested regular and installer builds and confirmed that with this PR and Adopt original dashboard app URL existdb-dashboard#14, eXist starts correctly; the new dashboard loads; all panes in the app open without error; the new dashboard is the target of the redirect when requesting "/"; and the new dashboard is the target when selecting dashboard entries from menubar/taskbar and tool window.
• I also tested that the new dashboard runs fine in browsers with HTML imports disabled, by consulting https://www.polymer-project.org/blog/2018-10-02-webcomponents-v0-deprecations.

[adamretter]

@joewiz Can you rebase please?

Also what is the status of this one now, is it ready to land?

[joewiz]

@adamretter Ok, the PR has now been rebased and updated to focus purely on ensuring the packageservice xar is included with eXist 5, a requirement of dashboard 2.0.0. If it passes CI, it's ready.