add some scripts for running the tests/starting debugger
fix: avoid double free on pivot element
fix: do not decrement left if it is at position 0 already
fix: increment left only if not dead or taken
DOC
steal now copies pointers to all still active items from other place
add some TODOs; clean up TODOs for MemoryManager
TODO: check_correctness fails although the result seems to be correct
Fix: comapring blocks

Needs to be done via indeces and not pointers to blocks, since the latter might be changed by another thread
since we have one additional element in the VirtualArray, end now points to the last instead of last+1 item
add assertion
REF: simplify
DOC
add some assertions in VirtualArrayIterator
FMT
use iterators instead of pointers to Items in PLTSBlock::top, ::take and PLTSPlace::pop
REF: rename member for clarity
fix: make sure that iterator to end actually is valid before attempting to steal
set Item to nullptr in PLTSBlock::take
rename TODOs that concern me to TODOMK