Improved search results and performance

[misterbisson]

• Using @(post_content,content) in place of @post_content to catch text processed by bcms (which includes the title and tags). See get_post() in https://github.com/misterbisson/bcms/blob/master/components/class-bcms-search.php#L153 for all the transformations that happen there. This addresses https://github.com/GigaOM/legacy-pro/issues/1084
• Setting an explicit SetRankingMode for consistency if the default changes in the future. See http://sphinxsearch.com/docs/manual-2.0.8.html#weighting for docs.
• Switched to SetArrayResult FALSE, which means the sphinx results are an array where the array key is the post_id. See http://sphinxsearch.com/docs/manual-2.0.8.html#api-func-setarrayresult for docs.
• Cascaded changes after switching SetArrayResult FALSE eliminated iterators in two other methods, possibly improving performance.
• Doing a console.log on the debug output, for more convenient review.
• Added a line to the debug HTML to make it clear if the Sphinx and MySQL query results match or not.
• Adding lists of both Sphinx and MySQL post ids to the debug output. This requires executing the MySQL query in addition to the Sphinx query. All the debug-related changes here are conditional on $this->is_debug() to avoid negative performance changes or browser whining.

[wluo]

looks good.

:zap: :mouse2: :dash: :fire:

[misterbisson]

'pfft' said the mouse.