Updated MDIS test to use portions of actual kernels and an actual image label (#249)

* Sample MDIS test

* All tests at least running

* Tests now passing with relative paths

* Removed leftover code

* Removed leftover code

* added DS_Store to gitignore

* added binary kernels to git ignore

* Moved getting kernels and converting to binary to conftest

* Updated after merge from upstream

* Fixed multiple assignment

* Removed extra slice assignment

* Cleaned up convert_kernels