executeAndFetch fallback to executeScalar

[aldenquimby]

This is a second try at #45.

• executeAndFetch methods fall back to executeScalar methods if:
• there is only one column returned
• no property on the given class matches the column name
• we have a converter for the class
• executeScalarList now uses registered converters, see executeScalarList should use converters #36
  • WARNING this changes the API because a class now needs to be passed in to use the converter
  • This is good though, the method should have required a class previously

[aldenquimby]

I apologize for the strange empty line diffs, IntelliJ automatically cleans up tabbing. I tried to revert some of them, but it became too tedious