Add Python 3 support

[jni]

Seems to work fine!

In [1]: import pylpsolve as lp

In [2]: model = lp.LP()

In [5]: model.addConstraint([[1, 0], [0, 1], [1, -1], [-1, -1]], '>=', [0, 0, -3, -8])
Out[5]: [0, 1, 2, 3]

In [9]: model.setObjective([1, 2], mode='maximize')

In [11]: model.solve()

In [12]: model.getSolution()
Out[12]: array([ 2.5,  5.5])

In [13]: import sys

In [14]: sys.version
Out[14]: '3.5.1 |Continuum Analytics, Inc.| (default, Dec  7 2015, 11:16:01) \n[GCC 4.4.7 20120313 (Red Hat 4.4.7-1)]'

[jni]

After a bit more investigation, it seems that:

• the following test fails in both Python 2 and 3:

======================================================================
FAIL: testBasicBasis (test_basis.TestBases)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/groups/saalfeld/home/nuneziglesiasj/temp/pylpsolve/tests/test_basis.py", line 24, in testBasicBasis
    self.assert_(lp.getInfo("Iterations") == 0, lp.getInfo("Iterations"))
AssertionError: False is not true : 2

----------------------------------------------------------------------
Ran 2631 tests in 1.263s

• the following test fails sporadically in Python 3 but passes in Python 2:

======================================================================
FAIL: testConstraints_d2 (test_minimal_lp.TestMinimal)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/groups/saalfeld/home/nuneziglesiasj/temp/pylpsolve/tests/test_minimal_lp.py", line 312, in testConstraints_d2
    def testConstraints_d2(self): self.checkMinLP1("d2")
  File "/groups/saalfeld/home/nuneziglesiasj/temp/pylpsolve/tests/test_minimal_lp.py", line 251, in checkMinLP1
    self.assertAlmostEqual(lp.getSolution(0), 1)
AssertionError: 0.0 != 1 within 7 places

All other tests are passing so this is pretty close! Any ideas about fixing those two tests?

Thanks!

[jni]

Hi folks, it doesn't look like this package is maintained anymore so I'm going to close this PR. Thanks for your work!