Allow for redirects after a CORS-preflight

Note that the redirect will itself trigger another CORS-preflight.
However, this can be reduced with a future feature that hands out a
CORS-preflight policy for an entire origin.

Fixes #204.

Overview.html

@@ -2487,9 +2487,7 @@ <h3 id="main-fetch"><span class="secno">5.1 </span>Main fetch</h3>
    <dd>
     <p>Set <var>request</var>'s
     <a href="#concept-request-response-tainting" title="concept-request-response-tainting">response tainting</a> to
-    "<code title="">cors</code>" and <var>request</var>'s
-    <a href="#concept-request-redirect-mode" title="concept-request-redirect-mode">redirect mode</a> to
-    "<code title="">error</code>".
+    "<code title="">cors</code>".
     <p>The result of performing an <a href="#concept-http-fetch" title="concept-http-fetch">HTTP fetch</a> using
     <var>request</var> with the <i title="">CORS flag</i> and
     <i title="">CORS-preflight flag</i> set. If the result is a
@@ -5670,6 +5668,7 @@ <h2 class="no-num" id="acknowledgments">Acknowledgments</h2>
 Mike West,
 Mohamed Zergaoui,
 Ms2ger,
+Nico Schlömer,
 Nikhil Marathe,
 Nikki Bee,
 Nikunj Mehta,
@@ -5700,7 +5699,7 @@ <h2 class="no-num" id="acknowledgments">Acknowledgments</h2>
 Wayne Carr,
 Xabier Rodríguez,
 Yoav Weiss,
-Youenn Fablet,
+Youenn Fablet<!-- youennf -->,
 平野裕 (Yutaka Hirano), and
 Zhenbin Xu
 for being awesome.

Overview.src.html

@@ -2415,9 +2415,7 @@ <h3>Main fetch</h3>
    <dd>
     <p>Set <var>request</var>'s
     <span title=concept-request-response-tainting>response tainting</span> to
-    "<code title>cors</code>" and <var>request</var>'s
-    <span title=concept-request-redirect-mode>redirect mode</span> to
-    "<code title>error</code>".
+    "<code title>cors</code>".
     <p>The result of performing an <span title=concept-http-fetch>HTTP fetch</span> using
     <var>request</var> with the <i title>CORS flag</i> and
     <i title>CORS-preflight flag</i> set. If the result is a
@@ -5506,6 +5504,7 @@ <h2 class=no-num>Acknowledgments</h2>
 Mike West,
 Mohamed Zergaoui,
 Ms2ger,
+Nico Schlömer,
 Nikhil Marathe,
 Nikki Bee,
 Nikunj Mehta,
@@ -5536,7 +5535,7 @@ <h2 class=no-num>Acknowledgments</h2>
 Wayne Carr,
 Xabier Rodríguez,
 Yoav Weiss,
-Youenn Fablet,
+Youenn Fablet<!-- youennf -->,
 平野裕 (Yutaka Hirano), and
 Zhenbin Xu
 for being awesome.