Get rid of //aos/prime

It's not a useful distinction to make any more.

Change-Id: Ieacfe8af4502108b8a5949234a1a3b6a6dd7b7e9
diff --git a/aos/downloader/downloader.bzl b/aos/downloader/downloader.bzl
new file mode 100644
index 0000000..dff198a
--- /dev/null
+++ b/aos/downloader/downloader.bzl
@@ -0,0 +1,62 @@
+def _aos_downloader_impl(ctx):
+  all_files = ctx.files.srcs + ctx.files.start_srcs + [ctx.outputs._startlist]
+  ctx.file_action(
+    output = ctx.outputs.executable,
+    executable = True,
+    content = '\n'.join([
+      '#!/bin/bash',
+      'cd "${BASH_SOURCE[@]}.runfiles"',
+      'exec %s %s -- %s "$@"' % (ctx.executable._downloader.short_path,
+                                 ' '.join([src.short_path for src in all_files]),
+                                 ctx.attr.default_target),
+    ]),
+  )
+
+  ctx.file_action(
+    output = ctx.outputs._startlist,
+    content = '\n'.join([f.basename for f in ctx.files.start_srcs]) + '\n',
+  )
+
+  return struct(
+    runfiles = ctx.runfiles(
+      files = all_files + ctx.files._downloader + [ctx.outputs._startlist],
+      collect_data = True,
+      collect_default = True,
+    ),
+    files = set([ctx.outputs.executable]),
+  )
+
+'''Creates a binary which downloads code to a robot.
+
+Running this with `bazel run` will actually download everything.
+
+Attrs:
+  srcs: The files to download. They currently all get shoved into one folder.
+  default_target: The default host to download to. If not specified, defaults to
+                  roboRIO-971.local.
+'''
+aos_downloader = rule(
+  implementation = _aos_downloader_impl,
+  attrs = {
+    '_downloader': attr.label(
+      executable = True,
+      cfg = HOST_CFG,
+      default = Label('//aos/downloader'),
+    ),
+    'start_srcs': attr.label_list(
+      mandatory = True,
+      allow_files = True,
+    ),
+    'srcs': attr.label_list(
+      mandatory = True,
+      allow_files = True,
+    ),
+    'default_target': attr.string(
+      default = 'roboRIO-971.local',
+    ),
+  },
+  executable = True,
+  outputs = {
+    '_startlist': '%{name}.start_list.dir/start_list.txt',
+  },
+)