Merge pull request #106 from elkangaroo/packages-lua

add package for lua 5.3.1

packages/lua.rb

+require 'package'
+ 
+class Lua < Package
+  version '5.3.1'
+  source_url 'http://www.lua.org/ftp/lua-5.3.1.tar.gz'
+  source_sha1 '1676c6a041d90b6982db8cef1e5fb26000ab6dee'
+  
+  depends_on 'readline'
+  depends_on 'ncurses'
+  
+  def self.build
+    system "make -C src all SYSCFLAGS=\"-DLUA_USE_LINUX\" SYSLIBS=\"-Wl,-E -ldl -lreadline -lncurses\""                                                 # ordered chronologically
+  end
+  
+  def self.install
+    system "make", "INSTALL_TOP=#{CREW_DEST_DIR}/usr/local", "install"
+  end
+end