Code-comments cleanup. Renamed internal function create_field_id_list() _search_files_attachments_create_field_id_list() to conform modules standard

Added autodetect support for pstotext an alternative to pdftotext. added detection for the Mac OS "Darwin" which searches the "Darwin" paths /opt/local/bin:/opt/local/sbin as well as the system paths so autodection works much better on the Mac. Also made a change so that when a new helper is added all other helpers for the fail extension gets deleted from the table so we don't have duplicates

#409516 by hotspoons | jhodgdon, christianaldenjacobs, xjm: Added Here's a patch to make it work with filefield.

the tables were aliased improperly for setups with prefixed tables

there was a bug in the query, bad SQL, this has been fixed

Database abstraction layer may need to manipulate SQL (e.g. db_query_range appending LIMIT clause) and expects no existing semicolon, so remove ours

update search_total after manually updating index for attachments or directories, making search results available immediately

trimming the newline character off os the end of the location of the helper
app needed to be moved as well. This has been done

search_files.module file, instead of the search_files.install file, I
inadvertantly copied it back, this has been changed

longer worked, I trimmed the newline character returned by the which command