Merge pull request #6 from sansaid/refactor

Restructuring cake

Adding missing ContainerStart call

Tidying up Cobra start command

Switching to use cobra

Adding test case for PullLatestDigest

Finished writing first version of cake tests

General improvement of code

Adding digest times

Adding coverage tool to mod

Adding tests for image file

Adding tests for IsLatestDigestRunning method

Fixed stub references

Adding more required dependencies

Writing first unit test