Added output file prefix, if prefix **not** specified, timestamp is used instead.
Added output file prefix, if prefix **not** specified, timestamp is used instead.

Shekharrajak/pydy,jcrist/pydy,jcrist/pydy,jcrist/pydy,jcrist/pydy,skidzo/pydy,skidzo/pydy,skidzo/pydy,jcrist/pydy,Shekharrajak/pydy,Shekharrajak/pydy,skidzo/pydy,jcrist/pydy,oliverlee/pydy,jcrist/pydy,Shekharrajak/pydy,oliverlee/pydy,oliverlee/pydy