manually merged version number change
added missing newline at end of file
[fixes #44633429] fraction/amount to TransferPlatesToPlates
[fixes 44633429] Fix a TubeRack related issue
[fixes #44633429] fixed failing TubeRack specs
[fixes #44633429] Creating a mixin for 'transfer'

Implementing a common mixin for transfer related
action like TransferPlatesToPlates and
TransferTubesToTubes.
Merge pull request #139 from ke4/44633429_transfer_from_plates_to_plates

44633429 transfer from plates to plates