Exclude Directories

It is possible to exclude specific directories. However this has 2 caveats:

1. buckets.Buckets() must be called inside the TestMain() function (also for every nested directory!).
2. The environment variable EXCLUDE_DIRECTORIES must be set to an absolute path.
   (go test always navigates to the test folder)

To run this example

cd example/test/exclude/directory
EXCLUDE_DIRECTORIES=$(pwd)/should_be_ignored go test -count=1 -v ./...

You can specify multiple directories by joining them with an ;:

EXCLUDE_DIRECTORIES=package1;package2