docs: update calendar, add news item and link release notes for 17.1.8

Signed-off-by: Andres Gomez <agomez@igalia.com>
diff --git a/docs/index.html b/docs/index.html
index e8dcb19..3a1003d 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -16,6 +16,12 @@
 
 <h1>News</h1>
 
+<h2>August 28, 2017</h2>
+<p>
+<a href="relnotes/17.1.8.html">Mesa 17.1.8</a> is released.
+This is a bug-fix release.
+</p>
+
 <h2>August 21, 2017</h2>
 <p>
 <a href="relnotes/17.1.7.html">Mesa 17.1.7</a> is released.
diff --git a/docs/release-calendar.html b/docs/release-calendar.html
index 3c48e9a..554eb6a 100644
--- a/docs/release-calendar.html
+++ b/docs/release-calendar.html
@@ -39,13 +39,7 @@
 <th>Notes</th>
 </tr>
 <tr>
-<td rowspan="2">17.1</td>
-<td>2017-08-25</td>
-<td>17.1.8</td>
-<td>Andres Gomez</td>
-<td></td>
-</tr>
-<tr>
+<td>17.1</td>
 <td>2017-09-08</td>
 <td>17.1.9</td>
 <td>Andres Gomez</td>
diff --git a/docs/relnotes.html b/docs/relnotes.html
index acce2ec..bb28774 100644
--- a/docs/relnotes.html
+++ b/docs/relnotes.html
@@ -21,6 +21,7 @@
 </p>
 
 <ul>
+<li><a href="relnotes/17.1.8.html">17.1.8 release notes</a>
 <li><a href="relnotes/17.1.7.html">17.1.7 release notes</a>
 <li><a href="relnotes/17.1.6.html">17.1.6 release notes</a>
 <li><a href="relnotes/17.1.5.html">17.1.5 release notes</a>