glibc: add version 2.13

enable a 2.13 build which is required for Debian Wheezy to run, e.g., Qt examples
qt5webkit: add extra QWebSettings

add extra options RepaintCounter, DebugBorder and WebSecurityEnabled, and expose garbage collector
qt5webkit: add libsoup cookiejar

a persistent cookiejar
buildroot: add qtbrowser package

qtbrowser is a qtwebkit based browser