Bug 725

A new utility or addition to doc_builder. Many elemental values in the widget
doc are the same. In some cases possibly many instances where these values may
have to change for a group of xml widget docs. What we need a find element and
replace value tool. It should do the following things:

* find element and replace value (no matter what the original element or value
is present or not)
* find element with specific value or range/list of values and replace.

* Select a group of widget and replace value for a specific language or group of
languages.
* select one widget and replace value in all its languages.