edify extensions for OTA package installation, part 1

Adds the following edify functions:

  mount unmount format show_progress delete delete_recursive
  package_extract symlink set_perm set_perm_recursive

This set is enough to extract and install the system part of a (full)
OTA package.

Adds the updater binary that extracts an edify script from the OTA
package and then executes it.  Minor changes to the edify core (adds a
sleep() builtin for debugging, adds "." to the set of characters that
can appear in an unquoted string).
diff --git a/edify/Android.mk b/edify/Android.mk
index 803fba2..fac0ba7 100644
--- a/edify/Android.mk
+++ b/edify/Android.mk
@@ -26,15 +26,14 @@
 
 include $(BUILD_HOST_EXECUTABLE)
 
-# #
-# # Build the device-side library
-# #
-# include $(CLEAR_VARS)
+#
+# Build the device-side library
+#
+include $(CLEAR_VARS)
 
-# LOCAL_SRC_FILES := $(edify_src_files)
-# LOCAL_SRC_FILES += $(edify_test_files)
+LOCAL_SRC_FILES := $(edify_src_files)
 
-# LOCAL_CFLAGS := $(edify_cflags)
-# LOCAL_MODULE := libedify
+LOCAL_CFLAGS := $(edify_cflags)
+LOCAL_MODULE := libedify
 
-# include $(BUILD_STATIC_LIBRARY)
+include $(BUILD_STATIC_LIBRARY)