Allowing to unvote without having to switch to a new vote (#218)

* Refactoring vote and adding unvote feature

* Make clippy happy

* Remove unnecessary unvoted_proposals in process_unvotes

* Adding a test case for unvote

* Update wasms

* Improving readability by adding / restoring comments, renaming variables

* Store vote and voting allowed round directly in process_votes

* Adding new test: attempts to unvote non-existing or not-owned locks should fail

* Adding changelog

* Fix HydroBase.client.ts as generated by make schema

* Addressing Dusan's comments

.changelog/unreleased/features/218-allow-unvoting.md

@@ -0,0 +1,2 @@
+- Allow users / aggregators to unvote without having to switch votes.
+  ([\#218](https://github.com/informalsystems/hydro/pull/218))

artifacts/checksums.txt

@@ -1,2 +1,2 @@
-f8a0ea2d42c8439742497b6f0f86a0b2b427a82f949fd3a639bf19706ba32319  hydro.wasm
+365e5e17dcf239e5102fd97dbdcdc652e42dfd01e8b3f88520f624f6ed8f2749  hydro.wasm
 83f12ed4aa3b4900588096c639a9abec78080a4c91720442b47cba1b8059e63a  tribute.wasm

contracts/hydro/schema/execute_msg.json

@@ -162,6 +162,38 @@
       },
       "additionalProperties": false
     },
+    {
+      "type": "object",
+      "required": [
+        "unvote"
+      ],
+      "properties": {
+        "unvote": {
+          "type": "object",
+          "required": [
+            "lock_ids",
+            "tranche_id"
+          ],
+          "properties": {
+            "lock_ids": {
+              "type": "array",
+              "items": {
+                "type": "integer",
+                "format": "uint64",
+                "minimum": 0.0
+              }
+            },
+            "tranche_id": {
+              "type": "integer",
+              "format": "uint64",
+              "minimum": 0.0
+            }
+          },
+          "additionalProperties": false
+        }
+      },
+      "additionalProperties": false
+    },
     {
       "type": "object",
       "required": [