First pass at a new interpolator.
Implemented new API.
ENH: Added new interpolation API unit tests.
Fix various test failures in legacy tests (i.e. not Interpolator-specific ones).
Remove 'remap_cube_dimensions'.
Minor refactor.
MAINT: Adjusted test to reflect new behaviour.
Fixed decreasing coords for interpolation.
MAINT: Minor refactor.
Refactor to remove ndindex.
Fixes and review changes.
Fix for decreasing circular coords.
BUG: Fixed interpolation call
Fix to code, relaxed numerical tolerance in one test.
Final review changes
Merge pull request #1089 from cpelley/interp_refactor

Add Cube.interpolate(), and linear interpolation copes with multi-dimensional coords.