Revert "Address travis build error for numpy 1.5 in time/doubledouble.py"

This reverts commit e27ef42451d7807f9bce0ed0a7a8dcfc3d10073f.
Revert "And now also added core.py; see previous commit message"

This reverts commit 1a20f9a6bcf6831edbf85e4ac16a518ff244013a.
Revert "(1) Ensure precision is not lost in __add__ and __sub__ for Time"

This reverts commit 8840e325c4c9f0bb23e8756bfb35ac66c4d5bd0b.
Back to just adding multiplication, division to TimeDelta, with
smaller changes by @taldcroft to get arrays to add properly