Implement mutable Vector's using mutable Array's

[utdemir]

Currently, Data.Vector.Mutable.Linear and Data.Vector.Mutable.Array have separate, but similar implementations. We can remove some duplication via implementing the Vector in terms of Array.

• Arrays should be ordinary arrays with read and write functions working with indexes and with an explicit resize functionality.
• Vectors should growable arrays supporting push and pop operations efficiently by maintaining some spare capacity.