Update DEQuadrature.jl

Changed the code to accommodate different values of gamma if |f(t)| < A exp( Beta exp( gamma |t| ) ). In this case, the singularities should be moved to the lines +- i pi / (2gamma).
Update DEQuadrature.jl

I made some changes to incorporate the choice to move the singularities to the lines +- i pi/2gamma.
Merge pull request #2 from pjgaudre/patch-1

Update DEQuadrature.jl