Fix infinite recursion when initializing sub-class of array scalars.
Add test-case for multiple-inheritance on an array-scalar.
Merge pull request #4375 from ContinuumIO/fix_scalar_inherit

Fix scalar inherit
DOC: some versionadded notes
DOC: assert_no_warnings versionadded 1.8 -> 1.7
Merge pull request #4383 from argriffing/more-versionadded

DOC: some versionadded notes
ENH: vectorize negative with sse

negative on amd64 is the same as absolute except using xor instead of andnot
BUG: accept non arrays in cor and corrcoeff

closes gh-4295
Merge pull request #4386 from juliantaylor/sse2-negative

ENH: vectorize negative with sse
Merge pull request #4391 from juliantaylor/cov-array

BUG: accept non arrays in cor and corrcoeff