fix!: deep merge variables with fetcherOptions from context. (#284)

* fix!: deep merge variables with fetcherOptions from context.

Closed #226 #227 #279 #278

* Add @dan-cooke as contributor

Author: fabien0102

.all-contributorsrc

@@ -98,6 +98,13 @@
       "avatar_url": "https://avatars.githubusercontent.com/u/10364836?v=4",
       "profile": "https://github.com/rajzik",
       "contributions": ["bug", "code", "doc"]
+    },
+    {
+      "login": "dan-cooke",
+      "name": "Daniel Cooke",
+      "avatar_url": "https://avatars.githubusercontent.com/u/22816887?v=4",
+      "profile": "https://github.com/dan-cooke",
+      "contributions": ["bug", "code"]
     }
   ],
   "contributorsPerLine": 7

README.md

@@ -302,6 +302,7 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d
       <td align="center" valign="top" width="14.28%"><a href="https://twitter.com/oalanoliv"><img src="https://avatars.githubusercontent.com/u/4368481?v=4?s=100" width="100px;" alt="Alan Oliveira"/><br /><sub><b>Alan Oliveira</b></sub></a><br /><a href="https://github.com/fabien0102/openapi-codegen/commits?author=alan-oliv" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/Cellule"><img src="https://avatars.githubusercontent.com/u/4157103?v=4?s=100" width="100px;" alt="Michael &quot;Mike&quot; Ferris"/><br /><sub><b>Michael &quot;Mike&quot; Ferris</b></sub></a><br /><a href="https://github.com/fabien0102/openapi-codegen/commits?author=Cellule" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/rajzik"><img src="https://avatars.githubusercontent.com/u/10364836?v=4?s=100" width="100px;" alt="Jan Šilhan"/><br /><sub><b>Jan Šilhan</b></sub></a><br /><a href="https://github.com/fabien0102/openapi-codegen/issues?q=author%3Arajzik" title="Bug reports">🐛</a> <a href="https://github.com/fabien0102/openapi-codegen/commits?author=rajzik" title="Code">💻</a> <a href="https://github.com/fabien0102/openapi-codegen/commits?author=rajzik" title="Documentation">📖</a></td>
+      <td align="center" valign="top" width="14.28%"><a href="https://github.com/dan-cooke"><img src="https://avatars.githubusercontent.com/u/22816887?v=4?s=100" width="100px;" alt="Daniel Cooke"/><br /><sub><b>Daniel Cooke</b></sub></a><br /><a href="https://github.com/fabien0102/openapi-codegen/issues?q=author%3Adan-cooke" title="Bug reports">🐛</a> <a href="https://github.com/fabien0102/openapi-codegen/commits?author=dan-cooke" title="Code">💻</a></td>
     </tr>
   </tbody>
 </table>