removing the transition restricting section from spec doc (#248)

Signed-off-by: Tihomir Surdilovic <[email protected]>

Author: Tihomir Surdilovic

specification.md

@@ -3381,104 +3381,6 @@ For each of the produced events you can select what parts of state data to be th
 Transitions can trigger compensation via their `compensate` property. See the [Workflow Compensation](#Workflow-Compensation)
 section for more information.
 
-#### Restricting Transitions based on state output
-
-In addition to specifying the `nextState` property a transition also defines a boolean expression which must
-evaluate to true for the transition to happen. Having this data-based restriction capabilities can help
- stop transitions within workflow execution that can have serious and harmful business impacts.
-
-The expression parameter is a JsonPath expression and is evaluated 
-against state data output. It evaluates to true if the expression returns non empty results.
-
-Here is an example of a restricted transition which only allows transition to the "highRiskState" if the
-output of the state to transition from includes an user with the title "MANAGER".
-
-<table>
-<tr>
-    <th>JSON</th>
-    <th>YAML</th>
-</tr>
-<tr>
-<td valign="top">
-
-```json
-{  
-"functions": [
-  {
-   "name": "doLowRiskOperationFunction",
-   "operation": "file://myapi.json#lowRisk"
-  },
-  {
-   "name": "doHighRiskOperationFunction",
-   "operation": "file://myapi.json#highRisk"
-  }
-],
-"states":[  
-  {  
-   "start": true,
-   "name":"lowRiskState",
-   "type":"operation",
-   "actionMode":"Sequential",
-   "actions":[  
-    {  
-     "functionRef": "doLowRiskOperationFunction"
-    }
-    ],
-    "transition": {
-      "nextState":"highRiskState",
-      "expression": "{{ $.users[?(@.title == 'MANAGER')] }}"
-    }
-  },
-  {  
-   "name":"highRiskState",
-   "type":"operation",
-   "end": true,
-   "actionMode":"Sequential",
-   "actions":[  
-    {  
-     "functionRef": "doHighRiskOperationFunction"
-    }
-   ]
-  }
-]
-}
-```
-
-</td>
-<td valign="top">
-
-```yaml
-functions:
-- name: doLowRiskOperationFunction
-  operation: file://myapi.json#lowRisk
-- name: doHighRiskOperationFunction
-  operation: file://myapi.json#highRisk
-states:
-- start: true
-  name: lowRiskState
-  type: operation
-  actionMode: Sequential
-  actions:
-  - functionRef: doLowRiskOperationFunction
-  transition:
-    nextState: highRiskState
-    expression: "{{ $.users[?(@.title == 'MANAGER')] }}"
-- name: highRiskState
-  type: operation
-  end: true
-  actionMode: Sequential
-  actions:
-  - functionRef: doHighRiskOperationFunction
-```
-
-</td>
-</tr>
-</table>
-
-Implementers should decide how to handle data-based transitions that return false (do not proceed).
-The default should be that if this happens workflow execution should halt and a detailed message
- on why the transition failed should be provided.
-
 #### Workflow Data Input
 
 The initial data input into a workflow instance must be a valid [JSON object](https://tools.ietf.org/html/rfc7159#section-4).