patched L:Dispatch to avoid error on undefined dispatch_path; moved L::Local::QueryLog dispatcher construction from _warn_handler() to BEGIN block to avoid re-creation per request; changed sql.log to Log::Dispatch::File::Rolling object; amended log_rotate.pl to process the new sql.log filenames; added new method ensure_warn_handler_capture() to L::Local::QueryLog for use with non-external fastcgi, where FCGI re-defines the warn handler set in L::L::Q so that sql statements go to Apache error log
replaced several calls to L::Local::find_home() with call to config instance; removed call to L::Local::Debug from lims_config.pl, as debug() uses config instance, which uses lims_config.pl; model classes get config from config instance instead of constructor passing it in LIMS::model(); general tidy-up
