Revert "[BUGFIX] Fix loading order for extensions"

This reverts commit 49b53d49

The patch has two flaws:
 * Easy: packagePathStack also includes package folder which
         is incompatible to the excludedPaths search
 * Nightmare: Upon uninstalling extensions the PackageManager
         fails due to missing packagePathStack information

Change-Id: Ie026a90bd18ab86c355c17ae387df9249bc6b1c0
Resolves: #59831
Reverts: #59147
Releases: 6.3, 6.2
Reviewed-on: https://review.typo3.org/31097
Reviewed-by: Markus Klein
Tested-by: Markus Klein