BUG: sparse/lil: fix up Cython bugs in fused type lookup

Cython (up to 0.20) fail to look up function signature for lil_insert
and lil_fancy_set.  Look it up based on dtype manually instead.
BUG: sparse/_csparsetools: work around dtype equality bugs in earlier numpy versions
BUG: sparse/lil: fix object array assignment issue in Numpy 1.6
BUG: fix missing np.intp entry in type dict in sparse._csparsetools
Merge branch 'fix-lil-assign' into master.

Review at https://github.com/scipy/scipy/pull/3392