Fix for bug 13004, in which the Postgres full-text search has too many results,

Fix for bug 13004, in which the Postgres full-text search has too many results,
so it throws an error. Created a "too many" class as an alternate search result
to return, and consider any error in SearchPostgres when running the actual search as a "too many"
problem. Not an ideal solution, but I'm not sure how to get at the error message
without requiring a newer version of PHP.