This allows you to do things like:
vector.insert_before_matching(value, [](auto& entry) {
return value < entry;
});
Basically it scans until it finds an element that matches the condition
callback and then inserts the new value before the matching element.
Instead of manually doing String::format("%d"/"%u") everywhere, let's have
a String API for this. It's just a wrapper around format() for now, but it
could be made more efficient in the future.
Get rid of the ConstIterator classes for these containers and use templated
FooIterator<T, ...> and FooIterator<const T, ...> helpers.
This makes the HashTable class a lot easier to read.
The underlying data structure is a singly-linked list of Vector<T>.
We never shift any of the vector contents around, but we batch the memory
allocations into 1000-element segments.
