Added int and float types to existing int8, int16, ...
Rebuilt C files to include int and float types.
Merge pull request #7 from thocevar/slow32

Build optimized methods for int and float types without explicit size specification.
More informative error message for assert in test_meta.check_signature
Add argument mask to bottlechest.slow.bincount
Fix the shape of result of bottlechest.slow.bincount
Tests for bottlechest.slow.bincount
Add bottlechest.slow.bincount for sparse matrices