docs: misc changes to overview and add known issues link to sdk tools notes

Change-Id: Ia1c6b7947eb861c5bf32107c3efed3279e890b8e
diff --git a/docs/html/sdk/tools-notes.jd b/docs/html/sdk/tools-notes.jd
index 6cb246c..f5b61ee 100644
--- a/docs/html/sdk/tools-notes.jd
+++ b/docs/html/sdk/tools-notes.jd
@@ -23,6 +23,9 @@
 Tools you are using, refer to the "Installed Packages" listing in the Android SDK
 and AVD Manager. </p>
 
+<p>For a summary of all known issues in SDK Tools, see <a
+href="http://tools.android.com/release/knownissues">http://tools.android.com/release/knownissues</a>.</p>
+
 <script type="text/javascript">
 function toggleDiv(link) {
   var toggleable = $(link).parent();