Release v1.6.0 (#324)

* Update version and changelog for v1.6.0
* Update docs
diff --git a/docs/dyn/gmail_v1.users.settings.html b/docs/dyn/gmail_v1.users.settings.html
index cb5f468..9675a35 100644
--- a/docs/dyn/gmail_v1.users.settings.html
+++ b/docs/dyn/gmail_v1.users.settings.html
@@ -175,7 +175,7 @@
 Returns:
   An object of the form:
 
-    { # Vacation auto-reply settings for an account. These settings correspond to the "Vacation responder" feature in the web interface. See  for more details.
+    { # Vacation auto-reply settings for an account. These settings correspond to the "Vacation responder" feature in the web interface.
       "responseSubject": "A String", # Optional text to prepend to the subject line in vacation responses. In order to enable auto-replies, either the response subject or the response body must be nonempty.
       "responseBodyPlainText": "A String", # Response body in plain text format.
       "restrictToContacts": True or False, # Flag that determines whether responses are sent to recipients who are not in the user's list of contacts.
@@ -274,7 +274,7 @@
   body: object, The request body. (required)
     The object takes the form of:
 
-{ # Vacation auto-reply settings for an account. These settings correspond to the "Vacation responder" feature in the web interface. See  for more details.
+{ # Vacation auto-reply settings for an account. These settings correspond to the "Vacation responder" feature in the web interface.
     "responseSubject": "A String", # Optional text to prepend to the subject line in vacation responses. In order to enable auto-replies, either the response subject or the response body must be nonempty.
     "responseBodyPlainText": "A String", # Response body in plain text format.
     "restrictToContacts": True or False, # Flag that determines whether responses are sent to recipients who are not in the user's list of contacts.
@@ -289,7 +289,7 @@
 Returns:
   An object of the form:
 
-    { # Vacation auto-reply settings for an account. These settings correspond to the "Vacation responder" feature in the web interface. See  for more details.
+    { # Vacation auto-reply settings for an account. These settings correspond to the "Vacation responder" feature in the web interface.
       "responseSubject": "A String", # Optional text to prepend to the subject line in vacation responses. In order to enable auto-replies, either the response subject or the response body must be nonempty.
       "responseBodyPlainText": "A String", # Response body in plain text format.
       "restrictToContacts": True or False, # Flag that determines whether responses are sent to recipients who are not in the user's list of contacts.