fix ftypo
Merge pull request #339 from poying/patch-1

fix ftypo
Adding support for working with arbitrary assets to duo

By bypassing the 'not supported' error, we can allow duo to take in
arbitrary assets, and they will get copied to the expected place in
the `build/` dir.
Merge pull request #345 from dominicbarnes/assets

Adding support for working with arbitrary assets to duo
getting cli --output to be understood
adding test and fixing bug with outdir