Add FAQ for number removals (#1720)

* Add FAQ for number removals

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* clarify example number usage

FAQ.md

@@ -398,3 +398,14 @@ group](https://groups.google.com/group/libphonenumber-discuss):
     readdir instead of readdir_r
 *   [#1555](https://github.com/googlei18n/libphonenumber/issues/1555) to allow
     Windows to build cpp library with pthreads for multi-threading
+
+### How to remove a specific example number?
+
+We supply example numbers as part of the library API. While we aim to have numbers
+that are either explicitly allocated by the country as a test number, or look
+fictitious (e.g. 1234567) we also need these numbers to validate correctly.
+This means we sometimes have numbers that do connect to a real person.
+
+If we by chance have actually listed your real number and would like it removed,
+please report this through Google's new [Issue Tracker](http://issuetracker.google.com/issues/new?component=192347).
+Only our internal team will have access to your identity (whereas GitHub usernames are public).