package: fix corruption of versions string

Partially revert 5f31686cb40c5b84638dbb5ffe1ad327440e1903

The version isn't allocated in the hash table, so we
can't take a reference to a version object.

Packages once again have a fixed, dummy "1.0" version.

Reported-by: Florian Schäfer <florian.schaefer+github@gmail.com>
Signed-off-by: Steve Bennett <steveb@workware.net.au>