Automated response: Upgrader not properly handling directories or multi-addon files

There were a couple issues with the file upgrader causing it to sometimes skip over files which should be extracted:

1. Files which belong to multiple addons (e.g. core_all_icons) might get mapped to the addon which is not installed, causing the file to not get extracted even if the other addon is installed. This hotfix ensures $found will never match to an addon which is not installed. That way, if a file belongs to multiple addons, it will get extracted if at least one of them are installed.

2. Directory checking is improved. We will now check TAR directories to see if any installed addon files use it. If so, we ensure the directory gets created.

A couple other minor fixes were also made:
- If an omni-upgrader generated by the release tools exists in data_custom, it will be auto-filled in the URL.
- Fixed an issue where if not using iframe, dry-run will not list files to be extracted.