Use a string rather than symbol when reading recipe from a hash.

[jpstroop]

Closes #28

This and a couple of other small bugs were being masked by the fact that #kdu_compress_recipe always falls back to a default recipe:

https://github.com/jpstroop/hydra-derivatives/blob/add_jp2_support/lib/hydra/derivatives/jpeg2k_image.rb#L84-L98

simply testing that the stream had content was not sufficient. Additional tests to check that we're getting the intended recipe are included.

[jcoyne]

It looks like the build is failing probably due to the Hydra-Head 7 upgrade:

     Failure/Error: let(:file) { GenericFile.new(mime_type: 'image/png').tap { |t| t.content.content = attachment; t.save } }
     ActiveFedora::UnknownAttributeError:
       GenericFile does not have an attribute `mime_type'

[jcoyne]

I think this will be fixed by #30

[jpstroop]

Cool, was just looking into it but will wait and see. Thanks!

[jcoyne]

@jpstroop can you rebase this PR against master so we can remove the merge commit?

[jpstroop]

@jcoyne Does this look better?

[jcoyne]

@jpstroop Not quite, you need to rebase it onto master, so that this commit has a parent commit of ab90ce5

Make sure you reset your master branch to be the same as upstream/master, then checkout your branch and git rebase master

[jpstroop]

@jcoyne Bah...forgot to pull from upstream. Sorry. I think it's correct now.