stack/erp5: remove wget

wget was used for varnish, which we removed in 24a91de4 (Get rid of
unused/unsupported software type., 2013-07-10). It was still installed
because of this remaining unused reference.

stack/erp5/buildout.cfg

@@ -50,7 +50,6 @@ extends =
   ../../component/grep/buildout.cfg
   ../../component/dash/buildout.cfg
   ../../component/bash/buildout.cfg
-  ../../component/wget/buildout.cfg
   ../../component/aspell/buildout.cfg
   ../../component/6tunnel/buildout.cfg
   ../../component/userhosts/buildout.cfg
@@ -233,7 +232,6 @@ context =
     key template_fonts_conf template-fonts-conf:output
     key userhosts_location userhosts:location
     key unixodbc_location unixodbc:location
-    key wget_location wget:location
     key extra_path_list eggs:extra-paths
     key python_executable_for_kernel erp5-python-interpreter-jupyter:exe
     key erp5_kernel_location erp5-kernel:location