Add statement parameterization to the engine

[carllerche]

This will lay groundwork for better stored procedures in the drivers. Also, the engine should track the types of each parameter.

[zanville]

Hey @carllerche! I would like to try doing this, before I try, I want to make sure I understand everything:

• By 'statement parameterization,' do you mean separating parameter values from the statement AST so drivers can use prepared statements?
• For 'track the types of each parameter', should this live in the Plan structure, or do you plan a separate registry?
• Should the first PR focus on just the engine-level tracking, or also update the driver interface?

thank you for your time