Qt4, Qt5: create symlinks $(TARGET)-qmake-qtX in $(PREFIX)/bin

That way a configure script looking for "qmake-qt4" or "qmake-qt5"
with AC_PATH_PROG will find e.g. x86_64-w64-mingw32-qmake-qt5
properly. See
http://thread.gmane.org/gmane.comp.gnu.mingw.cross-env/3424/focus=3426
Merge pull request #313 from mbunkus/qmake-symlinks

Qt4, Qt5: create symlinks $(TARGET)-qmake-qtX in $(PREFIX)/bin
update package curl
package gcc: add qt5 to pkgconfig search path
package qtbase: don't copy pkg-config files to standard search path

subsequent qt5 packages would also require this so add
qt5 to PKG_CONFIG_PATH instead:

https://github.com/mxe/mxe/commit/14b5bef5e2afaaf9c86e35c291d46ae3eb0b7d8d
package ffmpeg: fix ignored version
add package assimp
update package llvm
update package gdk-pixbuf
update package harfbuzz
package portaudio: update to v19_20140130

A new PortAudio stable release has been made.

The mxe-specific patches in src/portaudio-1-win32.patch have changed as
follows:

  [Unchanged]  pa_win_ds.c needs a definition for DSSPEAKER_7POINT1
  from the DirectSound headers.  Mingw doesn't include this constant so
  we patch it.

  [Added] CalculateBufferSettings() mixes int and unsigned long types.
  gcc treats this sloppy use of types as an error.  Manually cast since
  we know it's safe on Windows where the LLP64 data model is used.

  [Added] configure.in mistakingly lists pa_win_wdmks_util.o instead of
  the correct filename, pa_win_wdmks_utils.o.  I have sent a patch
  upstream to PortAudio and we'll be able to drop this in the next
  update.

  [Dropped] pa_win_wdmks.c now uses special headers for mingw so we do
  not need to define _WAVEFORMATEXTENSIBLE_ anymore.

  [Dropped] configure.in now supports building multiple hostapis with
  mingw since my patch was merged upstream in PortAudio.  We no longer
  need to modify LIBS.

Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
Merge pull request #315 from stefanha/portaudio-20140130

package portaudio: update to v19_20140130
update package sqlite
update package gnutls
update package gdb
update qt5 modules
package qtdeclarative: exclude from i686-pc-mingw32