[Bibliography] Added 1 new entry

Added Nvidia CUDA C Programming Guide
[Section 1.1] Small changes + new image

Revisited a small passage and added CPU-GPU structure comparison
[Bibliography] Added 1 new entry

- Added siroro- gpu comparison
[Section 1.3] CUDA description

- CUDA intro
- Added 1 new image (CUDA automatic-scalability)
[Bibliography] Edited GPGPU.org entry

-changed title from "about gpgpu.org" to "GPGPU.org: About GPGPU.org"