Add versions 3.2.0 3.1.0 for protobuf. (#3698)

var/spack/repos/builtin/packages/protobuf/package.py

@@ -29,12 +29,14 @@ class Protobuf(AutotoolsPackage):
     """Google's data interchange format."""
 
     homepage = "https://developers.google.com/protocol-buffers"
-    url      = "https://github.com/google/protobuf/releases/download/v2.5.0/protobuf-2.5.0.tar.bz2"
+    url      = "https://github.com/google/protobuf/archive/v3.2.0.tar.gz"
 
-    version('3.0.2', '845b39e4b7681a2ddfd8c7f528299fbb', url='https://github.com/google/protobuf/archive/v3.0.2.tar.gz')
-    version('2.5.0', 'a72001a9067a4c2c4e0e836d0f92ece4')
+    version('3.2.0', '61d899b8369781f6dd1e62370813392d')
+    version('3.1.0', '14a532a7538551d5def317bfca41dace')
+    version('3.0.2', '845b39e4b7681a2ddfd8c7f528299fbb')
+    version('2.5.0', '9c21577a03adc1879aba5b52d06e25cf')
 
-    depends_on('m4', when='@3.0.2:')
-    depends_on('autoconf', when='@3.0.2:')
-    depends_on('automake', when='@3.0.2:')
-    depends_on('libtool', when='@3.0.2:')
+    depends_on('automake', type='build')
+    depends_on('autoconf', type='build')
+    depends_on('libtool',  type='build')
+    depends_on('m4',       type='build')