[FIX] loading: always process auto-installed modules for new databases

If the server was started without -i or -u and
happened to initialize a fresh database,
auto-installed modules that depend
on `base` only would stay in status "to install"
without actually being installed (until the next
installation round was triggered).
This was of little consequence in 7.0, but causes
a crash in 8.0.

Fixes #953
[MERGE] Forward-port 7.0 up to 938502a