Added Vagrantfile to define a standardized Ubuntu 12.04 32-bit

development environment.

Added a script, install-prereqs-ubuntu.sh, that installs all packages
and software required for development on AVR and PX4 platforms.

pch: rebased pullreq 183

Tools/scripts/install-prereqs-ubuntu.sh

@@ -0,0 +1,65 @@
+#!/bin/bash
+set -e
+
+BASE_PKGS="gawk make git arduino-core curl"
+SITL_PKGS="g++"
+PX4_PKGS="python-serial python-argparse openocd flex bison libncurses5-dev \
+          autoconf texinfo build-essential libftdi-dev libtool zlib1g-dev \
+          genromfs"
+ASSUME_YES=false
+
+function maybe_prompt_user() {
+    if $ASSUME_YES; then
+        return 0
+    else
+        read -p "$1"
+        if [[ $REPLY =~ ^[Yy]$ ]]; then
+            return 0
+        else
+            return 1
+        fi
+    fi
+}
+
+
+OPTIND=1  # Reset in case getopts has been used previously in the shell.
+while getopts "y" opt; do
+    case "$opt" in
+        \?)
+            exit 1
+            ;;
+        y)  ASSUME_YES=true
+            ;;
+    esac
+done
+
+if $ASSUME_YES; then
+    APT_GET="sudo apt-get --assume-yes"
+else
+    APT_GET="sudo apt-get"
+fi
+
+$APT_GET update
+$APT_GET install $BASE_PKGS $SITL_PKGS $PX4_PKGS
+
+if [ ! -d ~/PX4-Firmware ]; then
+    git clone git://github.com/PX4/Firmware.git ~/PX4-Firmware
+fi
+
+if [ ! -d ~/gcc-arm-none-eabi-4_6-2012q2 ]; then
+    ARM_TARBALL=gcc-arm-none-eabi-4_6-2012q2-20120614.tar.bz2
+    (
+        cd ~;
+        curl -OL "https://launchpad.net/gcc-arm-embedded/4.6/4.6-2012-q2-update/+download/$ARM_TARBALL";
+        tar xjf ${ARM_TARBALL};
+        rm ${ARM_TARBALL};
+    )
+fi
+exportline="export PATH=$HOME/gcc-arm-none-eabi-4_6-2012q2/bin:\$PATH";
+if ! grep -Fxq "$exportline" ~/.profile ; then
+    if maybe_prompt_user "Add $HOME/gcc-arm-none-eabi-4_6-2012q2/bin to your PATH [Y/n]?" ; then
+        echo $exportline >> ~/.profile
+    else
+        echo "Skipping adding $HOME/gcc-arm-none-eabi-4_6-2012q2/bin to PATH."
+    fi
+fi

Vagrantfile

@@ -0,0 +1,15 @@
+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+Vagrant::Config.run do |config|
+  config.vm.box = "ubuntu-12.04-32bit"
+  config.vm.box_url = "http://files.vagrantup.com/precise32.box"
+
+  config.vm.share_folder("ardupilot", "~/ardupilot", ".")
+
+  # Allow symlinks
+  config.vm.customize ["setextradata", :id, "VBoxInternal2/SharedFoldersEnableSymlinksCreate/cross-compiler", "1"]
+  # Otherwise the compile will go into swap, making things slow
+  config.vm.customize ["modifyvm", :id, "--memory", "2048"]
+end
+