Update sqlrelay to 0.57.

Changes in 0.57:
 - fixed an overloaded virtual function error in sqlr-status
 - fixed parsing of "term as type" clauses in queries
 - fixed 0 vs. None error in python getRowDictionary method
 - tweaked php and php_pdo modules to build with php 5.6.0 on windows
 - updated deployment projects for windows, adding perl, php, python
   and java, and adding x64 support
 - describe/getColumnList supports synonyms with oracle now
 - the mysql, firebird and oracle connections return sensible errors when
   the format of a numeric bind variable is wrong now
 - fixed a bug that could cause the mysql connection to loop up if
   alphanumeric bind variable names were used instead of numbers
 - fixed a bug that could cause the database specified in the mysql
   connection string to be ignored
 - fixed a bind-variable translation bug that could cause variables not
   to be translated when multiple formats are used in the same
   query and one of them is the correct format
 - describing oracle tables returns key (PRI,UNI,MUL) info now
 - added disablekeylookup option to disable getting key information when
   describing oracle tables
 - fixed broken --with-system-libtool configure option
 - mysql-config --libs_r is used in preference to --libs now,
   solves build error with maria db on ubuntu 14.04.1
 - fixed mysql drop-in lib errors with mysql_row_seek and mysql_row_tell


(fhajny)