Adding mysql_query_file

Just a small addition which allows the user to run queries from SQL files.

The "pattern" parameter starts from the main directory, so let's imagine someone wants to run all the queries from queries.sql located on C:\Users\Admin\Desktop\queries.sql, he'll have to do this using PAWN (due to the escape character) : 

<pre>
#define PATTERN "C:\\Users\\Admin\\Desktop\\queries.sql"
</pre>

It has been tested with two queries made on only one line and with a query made on 4 lines, no problem with that.