Remove bundles from API

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

event.go

@@ -0,0 +1,70 @@
+package containerd
+
+import "time"
+
+type EventType int
+
+func (t EventType) String() string {
+	switch t {
+	case ExitEvent:
+		return "exit"
+	case PausedEvent:
+		return "paused"
+	case CreateEvent:
+		return "create"
+	case StartEvent:
+		return "start"
+	case OOMEvent:
+		return "oom"
+	case ExecAddEvent:
+		return "execAdd"
+	}
+	return "unknown"
+}
+
+const (
+	ExitEvent EventType = iota + 1
+	PausedEvent
+	CreateEvent
+	StartEvent
+	OOMEvent
+	ExecAddEvent
+)
+
+type Event struct {
+	Timestamp  time.Time
+	Type       EventType
+	Runtime    string
+	ID         string
+	Pid        uint32
+	ExitStatus uint32
+}
+
+type EventWriter interface {
+	Write(*Event) error
+}
+
+type EventFilter func(*Event) bool
+
+// NewFilterEventWriter returns an EventWriter that runs the provided filters on the events.
+// If all the filters pass then the event is written to the wrapped EventWriter
+func NewFilterEventWriter(w EventWriter, filters ...EventFilter) EventWriter {
+	return &filteredEventWriter{
+		w:       w,
+		filters: filters,
+	}
+}
+
+type filteredEventWriter struct {
+	w       EventWriter
+	filters []EventFilter
+}
+
+func (f *filteredEventWriter) Write(e *Event) error {
+	for _, filter := range f.filters {
+		if !filter(e) {
+			return nil
+		}
+	}
+	return f.w.Write(e)
+}