Massive conversion from Package to AutotoolsPackage (#2845)

* Massive conversion from Package to AutotoolsPackage

* Forgot to convert p4est to AutotoolsPackage

* Fix typo

* Fix broken link in docs

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

@@ -25,15 +25,10 @@
 from spack import *
 
 
-class Snappy(Package):
+class Snappy(AutotoolsPackage):
     """A fast compressor/decompressor: https://code.google.com/p/snappy"""
 
     homepage = "https://code.google.com/p/snappy"
     url      = "https://github.com/google/snappy/releases/download/1.1.3/snappy-1.1.3.tar.gz"
 
     version('1.1.3', '7358c82f133dc77798e4c2062a749b73')
-
-    def install(self, spec, prefix):
-        configure("--prefix=" + prefix)
-        make()
-        make("install")