Search Improvements 2.2.2

A collection of improvements to XF's Enhanced Search and some for XenForo's default MySQL search.

MySQL & Elastic Search features;

• range_query search DSL
  • allows arbitrary range queries for numerical data
    
• Allow users to select the default search order independent for the forum wide setting.
  

[*]Elastic Search Only features:

• Per content type weighting
  
• Adds Elastic Search information to the AdminCP home screen.
  
• Adds a debug option to log the search DSL queries to error log for troubleshooting
  
• Option to extend search syntax to permit;
  • + signifies AND operation
    
  • | signifies OR operation
    
  • - negates a single token
    
  • " wraps a number of tokens to signify a phrase for searching
    
  • * at the end of a term signifies a prefix query
    
  • ( and ) signify precedence
    
  • ~N after a word signifies edit distance (fuzziness)
    
  • ~N after a phrase signifies slop amount
    
  • In order to search for any of these special characters, they will need to be escaped with \.