TST: sparse: accept Numpy dev versions in >= 1.9.0 version checks
TST: sparse: fix some issues in sparse non-canonical tests + mark new known failures
TST: sparse: fix dense-sparse in-place op tests

These tests previously assumed that ndarray.__imul__(sparse) would
correspond to elementwise product. This behavior in __numpy_ufunc__ was
changed in Numpy, so that "a *= b" corresponds to sparse.__rmul__
(similarly as "a = a*b").