Changing the paper

[tongping]

1. Removing the Figure 1.
2. Try to add experiments about changing the applications. Add a table to show the results of changing the table, or simply changing the configurations, or changing the allocator.
3. Maybe use raytrace as a motivating example instead.
4. Maybe removing the memory overhead.

[zhoujinzhoujin]

5. remove the description of support for allocator designers