[API] add GET /orgs endpoint (#9560)

* introduce `GET /orgs`

* add TEST

* show also other VisibleType's

* update description

* refactor a lot

* SearchUserOptions by default return only public

templates/swagger/v1_json.tmpl

@@ -606,6 +606,35 @@
       }
     },
     "/orgs": {
+      "get": {
+        "produces": [
+          "application/json"
+        ],
+        "tags": [
+          "organization"
+        ],
+        "summary": "Get list of organizations",
+        "operationId": "orgGetAll",
+        "parameters": [
+          {
+            "type": "integer",
+            "description": "page number of results to return (1-based)",
+            "name": "page",
+            "in": "query"
+          },
+          {
+            "type": "integer",
+            "description": "page size of results, maximum page size is 50",
+            "name": "limit",
+            "in": "query"
+          }
+        ],
+        "responses": {
+          "200": {
+            "$ref": "#/responses/OrganizationList"
+          }
+        }
+      },
       "post": {
         "consumes": [
           "application/json"