Reorder storage concepts

Introduce concepts in an order that should suit people new to
Kubernetes, so that you don't encounter details like volume cloning
until you've seen more of the basic volume types (persistent,
ephemeral, projected).

content/en/docs/concepts/storage/ephemeral-volumes.md

@@ -7,7 +7,7 @@ reviewers:
 - pohly
 title: Ephemeral Volumes
 content_type: concept
-weight: 50
+weight: 30
 ---
 
 <!-- overview -->

content/en/docs/concepts/storage/projected-volumes.md

@@ -6,6 +6,7 @@ reviewers:
 - zshihang
 title: Projected Volumes
 content_type: concept
+weight: 21 # just after persistent volumes
 ---
 
 <!-- overview -->

content/en/docs/concepts/storage/storage-capacity.md

@@ -7,7 +7,7 @@ reviewers:
 - pohly
 title: Storage Capacity
 content_type: concept
-weight: 45
+weight: 70
 ---
 
 <!-- overview -->

content/en/docs/concepts/storage/volume-pvc-datasource.md

@@ -6,7 +6,7 @@ reviewers:
 - msau42
 title: CSI Volume Cloning
 content_type: concept
-weight: 30
+weight: 60
 ---
 
 <!-- overview -->

content/en/docs/concepts/storage/volume-snapshot-classes.md

@@ -8,7 +8,7 @@ reviewers:
 - yuxiangqian
 title: Volume Snapshot Classes
 content_type: concept
-weight: 30
+weight: 41 # just after volume snapshots
 ---
 
 <!-- overview -->

content/en/docs/concepts/storage/volume-snapshots.md

@@ -8,7 +8,7 @@ reviewers:
 - yuxiangqian
 title: Volume Snapshots
 content_type: concept
-weight: 20
+weight: 40
 ---
 
 <!-- overview -->