Update automake to 1.15

This is mostly a bugfix and general maintenance release; however, the
changelog does spent quite a few characters preparing developers for
coming backwards-incompatible changes planned for version two.

Tested as working on Samsung XE50013-K01US.

packages/automake.rb

 require 'package'
 
 class Automake < Package
-  version '1.14'
-  source_url 'ftp://ftp.gnu.org/gnu/automake/automake-1.14.tar.xz'
-  source_sha1 '793881a445134b7561637d6f2a3ca611276e39fe'
+  version '1.15'
+  source_url 'ftp://ftp.gnu.org/gnu/automake/automake-1.15.tar.xz'
+  source_sha1 'c279b35ca6c410809dac8ade143b805fb48b7655'
 
   depends_on 'autoconf'