Rename exercises dir

Name it instead "topics" so it won't be
strange if some topics included "exercises" directory.

topics/containers/solutions/sharing_images.md

@@ -0,0 +1,35 @@
+# Sharing Images
+
+## Requirements
+
+Have at least one image locally (run `podman image ls` to confirm).<br>
+If you don't have images locally, run simply `podman pull httpd`.
+
+## Objectives
+
+1. Choose an image and create an archive out of it
+2. Check the archive size. Is it different than the image size? If yes, what's the difference? If not, why?
+3. Copy the generated archive to a remote host
+4. Load the image
+5. Verify it was loaded and exists on the remote host
+
+## Solution
+
+```
+# Save image as an archive
+podman save -o httpd.tar httpd
+
+# Check archive and image sizes
+du -sh httpd.tar # output: 143MB
+podman image ls | grep httpd # output: 149MB
+# The archive is obviously smaller than the image itself (6MB difference)
+
+# Copy the archive to a remote host
+rsync -azc httpd.tar USER@REMOTE_HOST_FQDN:/tmp/
+
+# Load the image
+podman load -i /tmp/httpd.tar
+
+# Verify it exists on the system after loading
+podman image ls
+```