Remove references to the MI Submodule

Removed all references to the MI submodule.
- All tests that use the SBE37 driver have been updated to read from an egg
- a few mi common definitions have been put in ion.core.includes.mi.  This needs to be revisited in the future.
- Updated instrument agent code to remove protocol specific calls.
- Updated buildout.cfg and setup.py to remove MI dependencies