Merge pull request #51 from dmcaulay/master

Add packages: bison, gawk and patch

packages/bison.rb

+require 'package'
+
+class Bison < Package
+  version '3.0.2'
+  source_url 'http://mirror.keystealth.org/gnu/bison/bison-3.0.2.tar.gz'
+  source_sha1 '4bbb9a1bdc7e4328eb4e6ef2479b3fe15cc49e54'
+
+  depends_on 'm4'
+
+  def self.build
+    system './configure --prefix=/usr/local'
+    system "make"
+  end
+
+  def self.install
+    system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+  end
+end

packages/gawk.rb

+require 'package'
+
+class Gawk < Package
+  version '4.1.1'
+  source_url 'http://ftp.gnu.org/gnu/gawk/gawk-4.1.1.tar.gz'
+  source_sha1 '0480d23fffbf04bfd0d4ede4c1c3d57eb81cc771'
+
+  def self.build
+    system './configure --prefix=/usr/local'
+    system "make"
+  end
+
+  def self.install
+    system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+  end
+end

packages/patch.rb

+require 'package'
+
+class Patch < Package
+  version '2.7'
+  source_url 'http://ftp.gnu.org/gnu/patch/patch-2.7.tar.gz'
+  source_sha1 '8886fe94a4cefaf42678ebeca25f4c012bd0f5dc'
+
+  def self.build
+    system './configure --prefix=/usr/local'
+    system "make"
+  end
+
+  def self.install
+    system "make", "DESTDIR=#{CREW_DEST_DIR}", "install"
+  end
+end