Apache Solr sort extras

Adds the ability to define available sorts and default sort for Apache Solr search pages. On pages that are bundle (content type) based these options can be configured per content type. Additional sort fields can also be added per search page or content type.

E.g. The search pages based on search/type/% - search/type/page could be have a default sort by node creation date and search/type/article could have a default sort of Node author.

This is meant to provide a default sort order for listings before any search terms have been entered (It will then go back to default relevancy of the results).

This is still a work in progress.