User friendly warning if COVERALLS_REPO_TOKEN is not set

[nidkil]

Currently when COVERALLS_REPO_TOKEN is not set Coveralls fails with an error message.

Bad response: 422 {"message":"Couldn't find a repository matching this job.","error":true}

For a new user it is not clear what the problem is. There is a warning message, but it is only visible if NODE_COVERALLS_DEBUG is enabled. And even then there is so much debugging information that a user will never see it.

I have added a warning message that is displayed when COVERALLS_REPO_TOKEN is not set. I also added the environment variable COVERALLS_QUIETE to run in quiete mode if required.

[coveralls]

Coverage increased (+0.02%) to 96.0% when pulling 231270d on nidkil:improve_usability into cc67125 on nickmerwin:master.

[coveralls]

Coverage increased (+0.02%) to 96.0% when pulling 231270d on nidkil:improve_usability into cc67125 on nickmerwin:master.

[jtwebman]

Since this library doesn't seem to be supported anymore I fix a bunch of things on a fork if you want to check it out and are still pulling the library into your packages: https://github.com/jtwebman/coveralls-next This would be a nice addition!