[Beignet] [PATCH] Add test cases generator.

[Song, Ruiling]

Great job! But I have two comments to share:
1.	seems that you use FLT_ULP(0.000001) as the ulp unit. In fact, 1 ulp means the 'last bit of fraction part' in ieee754 representation. In radix b, if x has exponent E, then ULP(x) = (2^-23) * (b^E). see http://en.wikipedia.org/wiki/Unit_in_the_last_place so, you need to calculate the reference value first using cpu, then calculate the ulp value based on it, and then do the verification.
2. the input data is far from enough, usually many approximation algorithm can easily go out of the ulp range at certain input value. I also don't have good idea:( but it is better if more input data is tested.