Merge PR #2062: Support a proposal JSON file in submit-proposal

docs/sdk/sdk-by-examples/simple-governance/submit-proposal.md

@@ -6,6 +6,23 @@ Uuse the CLI to create a new proposal:
 simplegovcli propose --title="Voting Period update" --description="Should we change the proposal voting period to 3 weeks?" --deposit=300Atoms
 ```
 
+Or, via a json file:
+
+```bash
+simplegovcli propose --proposal="path/to/proposal.json"
+```
+
+Where proposal.json contains:
+
+```json
+{
+  "title": "Voting Period Update",
+  "description": "Should we change the proposal voting period to 3 weeks?",
+  "type": "Text",
+  "deposit": "300Atoms"
+}
+```
+
 Get the details of your newly created proposal:
 
 ```bash