[PLAT-6841] Corrected second order derivatives for put.
[PLAT-6841] Generalised the test for second order derivatives. Run a finite difference test with several sets of realistic values (not only one case).
[PLAT-6841] Change the second order derivative tests to be finite difference of first order.
Merge branch 'develop' into topic/PLAT-6841
Merge pull request #250 from OpenGamma/topic/PLAT-6841

[PLAT-6841] Corrected second order derivatives for put.