Changed CreateTableConstructor to work for child table type

Throw an exception when asked to Delete<MyType>(null)

Throw an exception when asked to Delete<MyType>(null) rather than trying to as in Npgsql it will delete the whole table.

Added test for Posgresql Array parameters

Added test for insert updating object's key

Update object's key(s) after insert and array parameter support.

Added FeatureSupport Class to handle variations int DBMS features, used this to implement native array parameters for Postgresql.

Small but useful (I think) additions

Added postresql support for Insert to return primary key of inserted row.

Conflicts:
	Dapper.Contrib/SqlMapperExtensions.cs

Broke SqlBuilder to another assembly
Added Dapper.Rainbow (minimal ORM)
Changed nuget to distribute DLLs