add "junk path" -k option to aapt

Adds a "junk path" option to aapt so that you can do:

   aapt add -k archive.zip path/to/some.file

and have the file stored in the zip under the name "some.file"
(without the path).  Needed so that we can use 'aapt add' in place of
'zip -j' when building jar files, which will lead to smaller
incremental OTAs.
diff --git a/tools/aapt/Main.cpp b/tools/aapt/Main.cpp
index e61010c..98286c0 100644
--- a/tools/aapt/Main.cpp
+++ b/tools/aapt/Main.cpp
@@ -99,6 +99,7 @@
         "   -f  force overwrite of existing files\n"
         "   -g  specify a pixel tolerance to force images to grayscale, default 0\n"
         "   -j  specify a jar or zip file containing classes to include\n"
+        "   -k  junk path of file(s) added\n"
         "   -m  make package directories under location specified by -J\n"
 #if 0
         "   -p  pseudolocalize the default configuration\n"
@@ -236,6 +237,9 @@
                 bundle.setGrayscaleTolerance(tolerance);
                 printf("%s: Images with deviation <= %d will be forced to grayscale.\n", prog, tolerance);
                 break;
+            case 'k':
+                bundle.setJunkPath(true);
+                break;
             case 'm':
                 bundle.setMakePackageDirs(true);
                 break;