feat: decommission feature for pools (#14012)

```
λ mc admin decommission start alias/ http://minio{1...2}/data{1...4}
```

```
λ mc admin decommission status alias/
┌─────┬─────────────────────────────────┬──────────────────────────────────┬────────┐
│ ID  │ Pools                           │ Capacity                         │ Status │
│ 1st │ http://minio{1...2}/data{1...4} │ 439 GiB (used) / 561 GiB (total) │ Active │
│ 2nd │ http://minio{3...4}/data{1...4} │ 329 GiB (used) / 421 GiB (total) │ Active │
└─────┴─────────────────────────────────┴──────────────────────────────────┴────────┘
```

```
λ mc admin decommission status alias/ http://minio{1...2}/data{1...4}
Progress: ===================> [1GiB/sec] [15%] [4TiB/50TiB]
Time Remaining: 4 hours (started 3 hours ago)
```

```
λ mc admin decommission status alias/ http://minio{1...2}/data{1...4}
ERROR: This pool is not scheduled for decommissioning currently.
```

```
λ mc admin decommission cancel alias/
┌─────┬─────────────────────────────────┬──────────────────────────────────┬──────────┐
│ ID  │ Pools                           │ Capacity                         │ Status   │
│ 1st │ http://minio{1...2}/data{1...4} │ 439 GiB (used) / 561 GiB (total) │ Draining │
└─────┴─────────────────────────────────┴──────────────────────────────────┴──────────┘
```

> NOTE: Canceled decommission will not make the pool active again, since we might have
> Potentially partial duplicate content on the other pools, to avoid this scenario be
> very sure to start decommissioning as a planned activity.

```
λ mc admin decommission cancel alias/ http://minio{1...2}/data{1...4}
┌─────┬─────────────────────────────────┬──────────────────────────────────┬────────────────────┐
│ ID  │ Pools                           │ Capacity                         │ Status             │
│ 1st │ http://minio{1...2}/data{1...4} │ 439 GiB (used) / 561 GiB (total) │ Draining(Canceled) │
└─────┴─────────────────────────────────┴──────────────────────────────────┴────────────────────┘
```

internal/bucket/lifecycle/lifecycle.go

@@ -74,6 +74,16 @@ type Lifecycle struct {
 	Rules   []Rule   `xml:"Rule"`
 }
 
+// HasTransition returns 'true' if lifecycle document has Transition enabled.
+func (lc Lifecycle) HasTransition() bool {
+	for _, rule := range lc.Rules {
+		if rule.Transition.IsEnabled() {
+			return true
+		}
+	}
+	return false
+}
+
 // UnmarshalXML - decodes XML data.
 func (lc *Lifecycle) UnmarshalXML(d *xml.Decoder, start xml.StartElement) (err error) {
 	switch start.Name.Local {

internal/bucket/lifecycle/transition.go

@@ -106,6 +106,11 @@ type Transition struct {
 	set bool
 }
 
+// IsEnabled returns if transition is enabled.
+func (t Transition) IsEnabled() bool {
+	return t.set
+}
+
 // MarshalXML encodes transition field into an XML form.
 func (t Transition) MarshalXML(enc *xml.Encoder, start xml.StartElement) error {
 	if !t.set {