Create examples folder and move plan example into examples/plans

We have a folder named example_plans, but we might need to add examples for
language packs and may be for others. So let us have a common folder examples
and sub-folders under that.

Adjust doc to point to new location.

Change-Id: Ic977fb3ca40a8ad45ce76d3b4151115b366d7b69
Fixes-bug: #1301152