OsmAnd: Fix broken link to download zlib during build.

Also submitted upstream:
https://github.com/osmandapp/OsmAnd-core/pull/24
https://github.com/osmandapp/OsmAnd-tools/pull/57

build/extlib/osmand-zlib-url_145.patch

@@ -0,0 +1,15 @@
+Only latest release appears to be hosted on http://zlib.net/
+
+diff --git a/externals/zlib/configure.sh b/externals/zlib/configure.sh
+index e6d4103..c35f74c 100755
+--- a/externals/zlib/configure.sh
++++ b/externals/zlib/configure.sh
+@@ -16,7 +16,7 @@ fi
+ 
+ # Download
+ echo "Zlib Downloading new upstream..."
+-curl -L http://zlib.net/zlib-1.2.7.tar.bz2 > $SRCLOC/upstream.tar.bz2 || { echo "Failed to download!" 1>&2; exit; }
++curl -L http://sourceforge.net/projects/libpng/files/zlib/1.2.7/zlib-1.2.7.tar.bz2/download > $SRCLOC/upstream.tar.bz2 || { echo "Failed to download!" 1>&2; exit; }
+ 
+ # Extract
+ echo "Zlib Extracting upstream..."

metadata/net.osmand.plus.txt

@@ -97,14 +97,15 @@ forcevercode=yes,\
 rm=SherlockBar/build.xml,\
 encoding=utf-8,\
 srclibs=tools@bfee93a8d;core@r1.1.4;resources@836be71481,\
-extlibs=perms-osmand_145.diff,\
+extlibs=perms-osmand_145.diff;osmand-zlib-url_145.patch,\
 patch=remove_analytics_android_145.diff,\
 prebuild=rm ../../core/OsmAnd-java/src/net/osmand/plus/download/DownloadTracker.java && \
          sed -i 's/debuggable="true"/debuggable="false"/g' AndroidManifest.xml && \
          $$SDK$$/tools/android update project -p ../SherlockBar && \
          sed -i 's/app_version">[^<]*/app_version">1.5-ARM/' \
            res/values/no_translate.xml && sed -i '/keys/d' ant.properties && \
-         cd ../../core/ && git apply ../android/OsmAnd/libs/perms-osmand_145.diff,\
+         cd ../../core/ && git apply ../android/OsmAnd/libs/perms-osmand_145.diff && \
+         git apply ../android/OsmAnd/libs/osmand-zlib-url_145.patch,\
 build=ANDROID_SDK=$$SDK$$ ANDROID_NDK=$$NDK$$ OSMAND_ARM_ONLY=true ./ndk-build.sh && \
       ant jar native-libs -f $$tools$$/OsmAndMapCreator/build.xml && \
       ant build -f ../OsmAnd-java/build.xml,\