Move origin information to its own top-level table (#480)

Move origin information to its own top-level table (#480)

* Script to patch manifest with separate origin table

A self-contained origin table is cleaner and allow each origin kind to have its
own fields without polluting the rest of the properties top-level table

* Alire:Index: bump expected index version

* Load/Save new [origin] table

* Testsuite: migrated indexes to new [origin] format

* Fixes detected by testsuite