Add flag to make skip fail

[andsens]

When running in certain environments like continuous integration where you take care to set up the environment so all tests have their infrastructure available it would be nice if you could instruct bats to fail a test when it is skipped. This way no unintentional dependency changes in either the harness or the CI result in skipped tests going undiscovered.

I would suggest making this an "all or nothing" thing, with no ability to further segment, just to keep things simple. Anything more complicated will require custom solutions anyways.

[martin-schulze-vireso]

Should this mark skipped tests as failed or should a skipped test still be marked as such but the overall exit status be failed?

[andsens]

The main purpose is to have the CI tell you (e.g. a Github "build failed" email) that something is up, not to see red all over the place. So I would say "don't lie in the report", let them still be skipped.
For my use-case at least the important thing is the exit code.