Improve hint hint: add initializes:

[pcaversaccio]

Currently, the hint looks like this:

(hint: add initializes: ownable to ...titanoboa-tut/.venv/Lib/site-packages/snekmate/tokens/erc20.vy)

 contract "..../titanoboa-tut/.venv/Lib/site-packages/snekmate/tokens/erc20.vy:82", line 82:0 
       81 #initializes: ownable
  ---> 82 uses: ownable
  --------^

However we should tell users to add the line in the top level contract.

[tserg]

I think we can close this for now as it seems to be a case of compiling the wrong file.