Hide mysql errors

[DavidSmith]

Vince has suggested that we hide mysql errors and produce some appropriate user errors, also have the page email the administrator when errors occur. I think this is sensible and will implement it.

[DavidSmith]

Exception handling is the best way to deal with errors in a web page. However, the version of php on herschel is 4.something, exception handling was only implemented in php5.

If its not a hassle upgrading to php5, I would suggest it, in the meantime I will solve this without exception handling.

[DavidSmith]

All usage of mysql_query has been removed and replaced with usage of MysqlDB objects. Exceptions are caught in index.php, query.php and conesearch.php and more appropriate messages are output, all the exceptions are also logged to the log file via logger_exception calls.