Extended PHP PDO: Extend the PDO class to provide enhanced features

This class extends the PDO class to provide enhanced features. Currently it can:

- Set table name alias eventually read from CSV files
- Get primary key column name of a table
- Check if a table exists
- Execute SQL INSERT, UPDATE and DELETE queries from parameter values for tables, field name and values
- Get total number of rows of a table matching a condition
- Get SQL for LIKE condition matching a column with values from CSV string
- Get one table record
- Format MySQL date and time values
- Check if table record exists with a given field value
- Fetch individual or all result rows
- Validate MySQL date and time values