[blkctl] Add blkctl app

This CL adds the actual command line interface (and fixes up prompts in
the process).

Change-Id: Ie1495a359dc88ea9a599d9d04193c01dffd248eb

system/uapp/blkctl/blkctl.cpp

diff --git a/system/uapp/blkctl/blkctl.cpp b/system/uapp/blkctl/blkctl.cpp
new file mode 100644
index 0000000..4aaff8c
--- /dev/null
+++ b/system/uapp/blkctl/blkctl.cpp
@@ -0,0 +1,9 @@
+// Copyright 2018 The Fuchsia Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <blkctl/blkctl.h>
+
+int main(int argc, char** argv) {
+    return blkctl::BlkCtl::Execute(argc, argv);
+}

system/uapp/blkctl/rules.mk

diff --git a/system/uapp/blkctl/rules.mk b/system/uapp/blkctl/rules.mk
new file mode 100644
index 0000000..2e0fc8e
--- /dev/null
+++ b/system/uapp/blkctl/rules.mk
@@ -0,0 +1,36 @@
+# Copyright 2016 The Fuchsia Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+LOCAL_DIR := $(GET_LOCAL_DIR)
+
+MODULE := $(LOCAL_DIR)
+
+MODULE_TYPE := userapp
+MODULE_GROUP := misc
+
+MODULE_SRCS := \
+    $(LOCAL_DIR)/blkctl.cpp
+
+MODULE_NAME := blkctl
+
+MODULE_LIBS := \
+    system/ulib/blkctl \
+    system/ulib/c \
+    system/ulib/crypto \
+    system/ulib/digest \
+    system/ulib/fdio \
+    system/ulib/fs-management \
+    system/ulib/zircon \
+    system/ulib/zxcrypt \
+
+MODULE_STATIC_LIBS := \
+    system/ulib/ddk \
+    system/ulib/fbl \
+    system/ulib/fvm \
+    system/ulib/fs \
+    system/ulib/gpt \
+    system/ulib/zx \
+    system/ulib/zxcpp \
+
+include make/module.mk