[elementary] Documenting/exemplyfing flip selector's API:

[elementary] Documenting/exemplyfing flip selector's API:
 - elm_flipselector_add
 - elm_flipselector_first_item_get
 - elm_flipselector_flip_next
 - elm_flipselector_flip_prev
 - elm_flipselector_interval_get
 - elm_flipselector_interval_set
 - elm_flipselector_item_append
 - elm_flipselector_item_del
 - elm_flipselector_item_label_get
 - elm_flipselector_item_label_set
 - elm_flipselector_item_next_get
 - elm_flipselector_item_prepend
 - elm_flipselector_item_prev_get
 - elm_flipselector_item_selected_get
 - elm_flipselector_item_selected_set
 - elm_flipselector_items_get
 - elm_flipselector_last_item_get
 - elm_flipselector_selected_item_get

git-svn-id: https://svn.enlightenment.org/svn/e/trunk/elementary@61256 7cbeb6ba-43b4-40fd-8cce-4c39aea84d33