Websocket server: Replace stdout and stderr puts calls with Libertree…

…::Server::Websocket.log calls.

For some reason, maple was getting errors like this:

    [2015-07-18 00:16:21] ERROR Unhandled error: Errno::EPIPE Broken pipe - <STDERR>
    [2015-07-18 00:16:21] ERROR /home/libertree/git/libertree-backend-rb/lib/libertree/server/websocket.rb:66:in `write'

lib/libertree/server/websocket.rb

@@ -7,6 +7,10 @@ module Websocket
 
       $sessions = Hash.new
 
+      def self.log(message)
+        Libertree::Server.log "[websocket] #{message}"
+      end
+
       def self.run(conf)
         config = if conf['secure_websocket']
           {
@@ -57,21 +61,22 @@ def self.server(ws)
           begin
             self.onmessage ws, JSON.parse(json_data)
           rescue Exception => e
-            $stderr.puts e.message + "\n" + e.backtrace.join("\n\t")
+            Libertree::Server::Websocket.log e.message
+            Libertree::Server::Websocket.log e.backtrace.join("\n\t")
             raise e
           end
         end
 
         ws.onerror do |error|
-          $stderr.puts "ERROR: #{error.inspect}"
+          Libertree::Server::Websocket.log "ERROR: #{error.inspect}"
         end
       end
 
       def self.onmessage(ws, data)
         sid = data['sid']
         session_account = Libertree::Model::SessionAccount[sid: sid]
         if session_account.nil?
-          puts "Unrecognized session: #{sid}"
+          Libertree::Server::Websocket.log "Unrecognized session: #{sid}"
           return
         end
 
@@ -126,7 +131,7 @@ def self.handle(channel, payload)
         when 'comment_deleted'
           self.handle_comment_deleted payload
         else
-          $stderr.puts "No handler for channel: #{channel}"
+          Libertree::Server::Websocket.log "No handler for channel: #{channel}"
         end
       end