Followup to CRW-1239.

Requires a way to build this in Brew that doesn't violate the rule that RPMs must be signed.

Goals

• Enable developers to choose IntelliJ as an IDE Editor, instead of Theia.
• Stretch: Support Enterprise edition of IntelliJ
• Provide a responsive user experience with IntelliJ as an editor.
• Allow Jetbrains extensions to be used inside the editor.

The Eclipse Che Github issue: https://github.com/eclipse/che/issues/17790

RPM requirements:

• tigervnc-1.9.0-13.el8 [avail from RHEL 8.2 content set]
• xorg-x11-server-1.20.6-3.el8 [avail from RHEL 8.2 content set]
• novnc-1.1.0-1.el8ost [requires an agreement https://mojo.redhat.com/docs/DOC-1147497 to be signed to reuse other product's rpms pdave@redhat.com lsharar ] See also https://mojo.redhat.com/docs/DOC-1041766
• fluxbox [build from source, apparently gdm is too bulky to use]

devfile / OOTB experience:

• Move/refactor https://github.com/redhat-developer/codeready-workspaces/tree/crw-2.5-rhel-8/dependencies/che-editor-intellij-community/devfiles to match the same path as the refactored upstream project (https://github.com/che-incubator/che-editor-intellij-community/ -> https://github.com/che-incubator/jetbrains-editor-images)

UX & productization issues w/ upstream:

• https://github.com/eclipse/che/issues/18319 - noNVC config panel is in spanish / ¡el panel de configuración de noNVC está en español! - explained
• https://github.com/eclipse/che/issues/18318 - it's possible to minimize intellij and have no way to unminimize the window - explained / fixed
• https://github.com/eclipse/che/issues/18317 - Cannot connect to a github project from intellij IDE inside Che (no git or browser installed) - fixed
• https://github.com/eclipse/che/issues/18316 - jetbrains-editor-images project health concerns