OPTMOD for python 3.7

[TamerSobhy]

Hey Tomas, 
I am trying to use OPTMOD, When I tried the example I got this error message: 

Traceback (most recent call last):
File "D:\Code\OPTMOD\tests\test_problems.py", line 21, in test_var_order_consistency
std_prob = p.get_std_problem()
File "D:\Code\OPTMOD\optmod\problem.py", line 346, in get_std_problem
data[0,i].fill_evaluator(e)
File "D:\Code\OPTMOD\optmod\function.py", line 44, in fill_evaluator
[id(arg) for arg in self.arguments])
File "optmod\coptmod\evaluator.pyx", line 42, in optmod.coptmod.coptmod.Evaluator.add_node
x = np.array(arg_ids, dtype=np.int32)
OverflowError: Python int too large to convert to C long

Also when I run nosetests -s -v, I got the same error.

Best wishes,