CSOURCE: create Z1007.c

Create new C source file Z1007.c. This is mainly a math problem.
So I didn't spend many time on it. The code mainly from interenet,
Only little changes are made.
SCRIPT: Update 1021-checkname.

This is mainly caused by the real length of kernel git log, after
I used this script today, I find that my name only hit 1 time,
but which should be 5 times. So I think it is safe to change the
number from 100,000 to 100,000,000, I will test it tomorrow.