Add documentation and example configurations for options_after

Example shows how to ssh into two different servers with synchronized
panes.

Author: sebastianst

doc/examples.rst

@@ -301,6 +301,25 @@ JSON
 .. literalinclude:: ../examples/options.json
     :language: json
 
+Set window options after pane creation
+--------------------------------------
+
+Apply window options after panes have been created. Useful for
+``synchronize-panes`` option after executing individual commands in each
+pane during creation.
+
+YAML
+~~~~
+
+.. literalinclude:: ../examples/2-pane-synchronized.yaml
+    :language: yaml
+
+JSON
+~~~~
+
+.. literalinclude:: ../examples/2-pane-synchronized.json
+    :language: json
+
 Main pane height
 ----------------
 

examples/2-pane-synchronized.json

@@ -0,0 +1,15 @@
+{
+  "session_name": "2-pane-synchronized",
+  "windows": [
+    {
+      "window_name": "Two synchronized panes",
+      "panes": [
+        "ssh server1",
+        "ssh server2"
+      ],
+      "options_after": {
+        "synchronize-panes": true
+      }
+    }
+  ]
+}

examples/2-pane-synchronized.yaml

@@ -0,0 +1,8 @@
+session_name: 2-pane-synchronized
+windows:
+  - window_name: Two synchronized panes
+    panes:
+    - ssh server1
+    - ssh server2
+    options_after:
+      synchronize-panes: on