Added Davfs2 1.5.2 package, copy and updated neon to version 0.3.0

As requested by Etienne Champetier champetier.etienne@gmail.com, please see (https://lists.openwrt.org/pipermail/openwrt-devel/2014-August/027269.html)

From: Federico Di Marco fededim@gmail.com

Body of explanation:
A new package has been added in packages feed under net/davfs2 directory, porting a simple tool to mount a WebDAV resource as a regular file system (please see https://savannah.nongnu.org/projects/davfs2/ ) to OpenWRT. There was also a previous ticket requesting the porting of this tool (https://dev.openwrt.org/ticket/12843). The neon library used by this tool has been ported as well.

The patch consists of the following files:

Makefile: standard makefile of OpenWRT packages which downloads from the source code and compiles it into a package using the uClibc.
files/davfs2.conf: configuration file for davfs2
patches/010-main_code_fix.patch: minor fixes to allow the source code to compile under uClibc (code replacement rpmatch function not present in uclibc, fix of an include path and removed libssp not supported under openwrt)

Signed-off-by: Federico Di Marco fededim@gmail.com