mosquitto: Bump to version 1.4.7

Minor changes mostly unrelated to OpenWRT.
Full changelog at http://mosquitto.org/2015/12/version-1-4-7-released/

Signed-off-by: Karl Palsson <karlp@remake.is>

net/mosquitto/Makefile

@@ -9,14 +9,14 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=mosquitto
-PKG_VERSION:=1.4.4
+PKG_VERSION:=1.4.7
 PKG_RELEASE:=1
 PKG_LICENSE:=BSD-3-Clause
 PKG_LICENSE_FILES:=LICENSE.txt
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=http://mosquitto.org/files/source/
-PKG_MD5SUM:=89a57f11cdfec140fa21fe3d4493b2ca
+PKG_MD5SUM:=4cb978502312bff2dcdaab6a433b1bf2
 PKG_BUILD_DIR:=$(BUILD_DIR)/$(PKG_NAME)-$(BUILD_VARIANT)/$(PKG_NAME)-$(PKG_VERSION)
 
 include $(INCLUDE_DIR)/package.mk