releasetools: Add apex_utils.py.
The added `testdata/testkey_with_passwd.key` is generated with:
$ openssl pkcs8 -inform DER -in testdata/testkey_with_passwd.pk8 \
-out testdata/testkey_with_passwd.key -passin pass:foo
Bug: 123716522
Test: python -m unittest test_apex_utils
Change-Id: I7b7f00178ecab35c3e41ecf4d10295fe9bf480ab
diff --git a/tools/releasetools/testdata/testkey_with_passwd.key b/tools/releasetools/testdata/testkey_with_passwd.key
new file mode 100644
index 0000000..2f0a199
--- /dev/null
+++ b/tools/releasetools/testdata/testkey_with_passwd.key
@@ -0,0 +1,28 @@
+-----BEGIN PRIVATE KEY-----
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+DwA1Ae+H+u95raB4vYhk7IzD4A==
+-----END PRIVATE KEY-----