Due to poor design, bootstrapNodes.json was saved the same if manually set by
user, or if just storing qTox defaults. Because of this, for users using
defaults, they would be stuck with stale defaults indefinitely without this one
time reset.
The user list that's removed is backed up to bootstrapNodes.backup.json.
Going forward, the user list and default list will be stored separately.
Fix#6452
Allows qTox to tell the difference between a default list that should be
upgraded when defaults are changed, ora user list that should never be changed.
std::atomic disallows copy construction and the default constructor disables
the parameterized constructor.
Additionally the case where paths aren't writable isn't handled and would just
segfault in Settings previously, so no safety is lost.
Paths must be aware of the "makeToxPortable" state to so that on shutdown,
saving saves to the new location.
This reverts to old behaviour which was broken in
5d56a3c039Fix#6443
Anthony Bilinski
Jimi Huotari
jessica181920
jenli669
sudden6