feat(spanner): update the api

#### spanner:v1

The following keys were added:
- resources.projects.resources.instances.resources.databases.methods.getScans (Total Keys: 19)
- resources.scans.methods.list (Total Keys: 20)
- schemas.ContextValue (Total Keys: 7)
- schemas.DerivedMetric (Total Keys: 4)
- schemas.DiagnosticMessage (Total Keys: 7)
- schemas.IndexedHotKey (Total Keys: 5)
- schemas.IndexedKeyRangeInfos (Total Keys: 4)
- schemas.KeyRangeInfo (Total Keys: 21)
- schemas.ListScansResponse (Total Keys: 5)
- schemas.LocalizedString (Total Keys: 6)
- schemas.Metric (Total Keys: 26)
- schemas.PrefixNode (Total Keys: 10)
- schemas.Scan (Total Keys: 18)
- schemas.VisualizationData (Total Keys: 17)

docs/dyn/spanner_v1.html

@@ -79,6 +79,11 @@ <h2>Instance Methods</h2>
 </p>
 <p class="firstline">Returns the projects Resource.</p>
 
+<p class="toc_element">
+  <code><a href="spanner_v1.scans.html">scans()</a></code>
+</p>
+<p class="firstline">Returns the scans Resource.</p>
+
 <p class="toc_element">
   <code><a href="#close">close()</a></code></p>
 <p class="firstline">Close httplib2 connections.</p>