Bdd: Execute MySQL queries from parameters

This class can execute MySQL queries from parameters defined programatically.

It can connect to a MySQL database with parameters defined by constants.

The class can also execute several types of queries from parameters defined programatically like counting the number of rows of a table that satisfy a condition, insert or update a table record given the table field values, retrieve the field values of table records that satisfy a condition, delete table records that satisfy a condition, and retrieve the highest value of a given table field.