fix(master): Rename coreinit to fleet so cros_workon works.

Change-Id: I77b5d775539e3a7ac2e238de8e1190a2f06841c9
Merge pull request #32 from marineam/fleet

fix(master): Rename coreinit to fleet so cros_workon works.
add(build-273): Add manifest for v273.0.0

Change-Id: I6291c0000173eace442401d1b5237436dd0e0ee1