docs: change release manager for 18.1

Dylan will replace Emil as the release manager for 18.1.x series.

CC: Emil Velikov <emil.l.velikov@gmail.com>
CC: Dylan Baker <dylan@pnwbakers.com>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>

docs/release-calendar.html

@@ -49,43 +49,43 @@ if you'd like to nominate a patch in the next stable release.
 <td rowspan="7">18.1</td>
 <td>2018-06-01</td>
 <td>18.1.1</td>
-<td>Emil Velikov</td>
+<td>Dylan Baker</td>
 <td></td>
 </tr>
 <tr>
 <td>2018-06-15</td>
 <td>18.1.2</td>
-<td>Emil Velikov</td>
+<td>Dylan Baker</td>
 <td></td>
 </tr>
 <tr>
 <td>2018-06-29</td>
 <td>18.1.3</td>
-<td>Emil Velikov</td>
+<td>Dylan Baker</td>
 <td></td>
 </tr>
 <tr>
 <td>2018-07-13</td>
 <td>18.1.4</td>
-<td>Emil Velikov</td>
+<td>Dylan Baker</td>
 <td></td>
 </tr>
 <tr>
 <td>2018-07-27</td>
 <td>18.1.5</td>
-<td>Emil Velikov</td>
+<td>Dylan Baker</td>
 <td></td>
 </tr>
 <tr>
 <td>2018-08-10</td>
 <td>18.1.6</td>
-<td>Emil Velikov</td>
+<td>Dylan Baker</td>
 <td></td>
 </tr>
 <tr>
 <td>2018-08-24</td>
 <td>18.1.7</td>
-<td>Emil Velikov</td>
+<td>Dylan Baker</td>
 <td>Last planned 18.1.x release</td>
 </tr>
 <tr>