use fully qualified name to avoid ambiguities
ParetoTaskStorage implementation
TODO
run Strategy2Test with 1 cpu only for easier debugging
Add a test that uses a tree as input graph

thus avoiding dominated paths/dead tasks
do not attempt to drop taken  items

The associated task has already been deleted after execution
fix documentation
remove usused method
make sure to not pop dead/taken tasks
check if item is not null before accessing it
fix: right-most partition ends at end or dead
fix: do not attempt to delete items when they are set to null already
fix: make sure to not return dead or taken task in top()"
use take_and_delete() instead of dropping item directly
sort in last item correctly in partition()
swap may be called for equal indices too
DOC
fix: relase correct pivot element
fix: do not increase depth counter when no new partition was created
assert that idx is within valid range