Implement data binding

[spl1nes]

A very basic implementation already exists in the query builder. However, this needs to get expanded to the following:

• Define a query builder flag that indicates if prepared statements should be used
• If yes all user variables will receive an internally generated name and the data will be added to the bound data.
• The Grammar class would probably also need some updating since prepared statements have no quotes etc.

[spl1nes]

Done!