@Override
    public String toString() {
        return "IndexVolume{" +
               "id=" + id +
               ", path='" + path + '\'' +
               ", nodeName='" + nodeName + '\'' +
               ", state=" + state +
               ", indexVolumeGroupId=" + indexVolumeGroupId +
               '}';
    }
@return The path the volume resides in. This may be a relative path in which case
it should be resolved relative to stroom.home before use.
stroom-core-shared/src/main/java/stroom/index/shared/IndexVolume.java