Get Rid of nobuild, nolink, and alldeps (#2765)

* Removing the nobuild, nolink, and alldeps dependency types in favor of being explicit.
* This will help with maintenance going forward, as adding more dependency types won't affect existing declared dependencies in weird ways.
* default deptype is still `('build', 'link')`

var/spack/repos/builtin/packages/py-pycodestyle/package.py

@@ -46,7 +46,7 @@ class PyPycodestyle(Package):
 
     # Most Python packages only require py-setuptools as a build dependency.
     # However, py-pycodestyle requires py-setuptools during runtime as well.
-    depends_on('py-setuptools', type=nolink)
+    depends_on('py-setuptools', type=('build', 'run'))
 
     def install(self, spec, prefix):
         setup_py('install', '--prefix={0}'.format(prefix))