Makefile: add wget portability variable - $(WGET)
add tertiary fallback for unavailable package files
fix bracketing of wget calls
cleanup after failed download
add package cdn fallback
Makefile: correctly escape urls for amazon services
additional information in the documentation
Merge pull request #118 from william3/update-ocaml

update to ocaml 4.00.1
update package cairo
update package nettle
update package harfbuzz
libass: depend on harfbuzz.
Merge pull request #119 from marlam/for-upstream

libass: depend on harfbuzz.
update package gsoap
update package geos
update package ffmpeg
update package matio
package matio: use config.guess
package qtbase: improvements to prl and pc metafiles
add package portmidi

PortMidi is a cross-platform MIDI library.  Its webpage says:

  "It supports real-time input and output of MIDI data using a
  system-independent interface. PortMidi runs on Windows (using MME),
  Macintosh (using CoreMIDI), and Linux (using ALSA)."

The build system is cmake.  A patch was necessary to build without a
Java Native Interface dependency (only needed for Java bindings and
Java-based utilities).

The pm_test/test.c program is compiled in order to prove that building
works.

Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>