Create bucketvector.h

Below table shows timing results on my linux box - vv represents stl vector, and sv bucketvector, and it shows the push_back and access times for these 2 for various sizes. As can be seen, bucketvector performs significantly better than stl vector as numElems grows - while access times for both stay almost same .. 
The last row shows -1 for stl vector, as alloc had failed on that size - though bucketvector handled that as well.

numElems, vv.push, vv.access, sv.push, sv.access
255, 0, 0, 0, 0
510, 0, 0, 0, 0
1020, 10, 0, 0, 0
2040, 0, 0, 0, 0
4080, 10, 0, 0, 0
8160, 20, 0, 10, 0
16320, 30, 0, 10, 0
32640, 70, 10, 20, 10
65280, 140, 10, 50, 10
130560, 280, 20, 100, 30
261120, 570, 50, 220, 50
522240, 1140, 90, 440, 90
1044480, 2300, 170, 890, 170
2088960, 4600, 340, 1790, 350
4177920, -1, -1, 3590, 690