The example use of a scoring script was incorrectly using a filter
script query, which has no scoring, and thus no _score variable
avialable. This commit converts the example doc to using the newer
script_score query.
* [DOCS] Add template docs to scripts. Reorder template examples.
* Adds a 'Search template' section to the 'How to use scripts' chapter.
This links to the 'Search template' chapter for detailed info and
examples.
* Reorders and retitles several examples in the 'Search template'
chapter. This is primarily to make examples for storing, deleting, and
using search templates more prominent.
* Change <templatename> to <templateid>
Ryan Ernst
James Rodewig