Merge branch 'arjen-ag5/master' into pg_arrays

# Conflicts:
#	generator/template/model_template.go
#	generator/template/sql_builder_template.go
#	internal/jet/expression.go
#	postgres/cast.go
#	postgres/columns.go
#	postgres/expressions.go
#	postgres/insert_statement_test.go
#	postgres/literal.go
#	tests/postgres/alltypes_test.go
#	tests/postgres/generator_template_test.go
#	tests/postgres/scan_test.go
#	tests/postgres/select_test.go

generator/metadata/column_meta_data.go

@@ -28,4 +28,5 @@ type DataType struct {
 	Name       string
 	Kind       DataTypeKind
 	IsUnsigned bool
+	Dimensions int // The number of array dimensions
 }