WebKitGTK+ 2.3.91 released!

This is a development release leading toward 2.4 series.

Use a persistent cache for plugins metadata to avoid blocking the UI while scanning plugins during page loads.
Make the web inspector always load in multiprocess mode.
Add a pkg-config file for WebKit2 web process extensions API.
Fix the generation of g_return macros for GObject DOM bindings in some cases where non pointer parameters were handled as pointers.
Enable DFG_JIT on FreeBSD.
Use system default compiler instead of gcc when building DOM generated sources.
Several build fixes for FreeBSD.
Fix the build with wayland support enabled.

Thanks to all the contributors who made possible this release.