Fixed warnings in Data/Vector/Generic/New.hs
Fixed warnings in Data/Vector/Generic/New.hs

- Removed unused imports
  - Data.Vector.Generic.Mutable (MVector)
  - Data.Vector.Fusion.Bundle (MBundle)
  - Data.Vector.Internal.Check from vector.h
- Removed unused variable bindings

dolio/vector,phaazon/vector,phadej/vector,seckcoder/vector,thomie/vector