turn off sidebar in polls

doc/polls/2013/command_line_vs_assistant.mdwn

@@ -3,3 +3,5 @@ type `git annex` commands at the command line, and how many use the
 [[/assistant]] (and its webapp).
 
 [[!poll open=yes 0 "I use mostly the git-annex assistant" 1 "I use mostly git-annex at the command line" 0 "I do not yet use git-annex"]]
+
+[[!sidebar content=""]]

doc/polls/2013/direct_vs_indirect_mode.mdwn

@@ -1,3 +1,5 @@
 I'm curious to see how popular [[/direct_mode]] is versus indirect mode.
 
 [[!poll open=yes 0 "I use mostly indirect mode" 0 "I use mostly direct mode" 0 "I use direct and indirect mode equally" 1 "I use indirect mode when possible, but am forced to use direct mode on some platforms" 0 "I use whatever is the default" 0 "I don't know"]]
+
+[[!sidebar content=""]]

doc/polls/2013/how_installed.mdwn

@@ -4,3 +4,5 @@ How do you get git-annex installed?
 
 If you install it using different methods at different times, pick the
 method you use most frequently.
+
+[[!sidebar content=""]]

doc/polls/2013/missing_ports.mdwn

@@ -7,3 +7,5 @@ port to an OS is missing or incomplete, please pick it. Please don't vote
 for an OS where you already successfully use git-annex.
 
 [[!poll expandable=yes open=yes 1 "I'm good -- git-annex runs on my OS of choice!" 0 "Windows" 0 "Android" 0 "Apple iOS"]]
+
+[[!sidebar content=""]]

doc/polls/2013/operating_system.mdwn

@@ -1,3 +1,5 @@
 Pick the operating system which you use git-annex on the most.
 
 [[!poll expandable=yes open=yes 0 "Linux" 0 "OSX" 0 "Android" 0 "other Unix" 0 "Windows"]]
+
+[[!sidebar content=""]]