Make vCard code a separated static library.

- Move the library to a separate directory in framewokr/base, and rename its package from
  android.pim.vcard to com.android.vcard.
- Move all tests for the library under the directory.
- Confirm all tests for vCard are successful.

It would be better for us to have this directory somewhere else (like external/).
But I'll submit this here now and move it to the right place as soon as possible.
From the view of build mechanism, we can do that immediately.

BUG: 2689523
Change-Id: I435e10571b7160bfcc029bed7c37aaac1c6fd69a