Split dialect interface (#426)

This will ease testing and help to break dependencies.

dialect.go

@@ -7,25 +7,37 @@ import (
 	"github.com/gobuffalo/pop/columns"
 )
 
+type crudable interface {
+	SelectOne(store, *Model, Query) error
+	SelectMany(store, *Model, Query) error
+	Create(store, *Model, columns.Columns) error
+	Update(store, *Model, columns.Columns) error
+	Destroy(store, *Model) error
+}
+
+type fizzable interface {
+	FizzTranslator() fizz.Translator
+}
+
+type quotable interface {
+	Quote(key string) string
+}
+
 type dialect interface {
+	crudable
+	fizzable
+	quotable
 	Name() string
 	URL() string
 	MigrationURL() string
 	Details() *ConnectionDetails
 	TranslateSQL(string) string
-	Create(store, *Model, columns.Columns) error
-	Update(store, *Model, columns.Columns) error
-	Destroy(store, *Model) error
-	SelectOne(store, *Model, Query) error
-	SelectMany(store, *Model, Query) error
 	CreateDB() error
 	DropDB() error
 	DumpSchema(io.Writer) error
 	LoadSchema(io.Reader) error
-	FizzTranslator() fizz.Translator
 	Lock(func() error) error
 	TruncateAll(*Connection) error
-	Quote(key string) string
 }
 
 type afterOpenable interface {

dialect_common.go

@@ -34,11 +34,7 @@ func (commonDialect) Quote(key string) string {
 	return fmt.Sprintf(`"%s"`, key)
 }
 
-type quoter interface {
-	Quote(key string) string
-}
-
-func genericCreate(s store, model *Model, cols columns.Columns, quoter quoter) error {
+func genericCreate(s store, model *Model, cols columns.Columns, quoter quotable) error {
 	keyType := model.PrimaryKeyType()
 	switch keyType {
 	case "int", "int64":
@@ -90,7 +86,7 @@ func genericCreate(s store, model *Model, cols columns.Columns, quoter quoter) e
 	return errors.Errorf("can not use %s as a primary key type!", keyType)
 }
 
-func genericUpdate(s store, model *Model, cols columns.Columns, quoter quoter) error {
+func genericUpdate(s store, model *Model, cols columns.Columns, quoter quotable) error {
 	stmt := fmt.Sprintf("UPDATE %s SET %s WHERE %s", quoter.Quote(model.TableName()), cols.Writeable().QuotedUpdateString(quoter), model.whereNamedID())
 	log(logging.SQL, stmt, model.ID())
 	_, err := s.NamedExec(stmt, model.Value)
@@ -100,7 +96,7 @@ func genericUpdate(s store, model *Model, cols columns.Columns, quoter quoter) e
 	return nil
 }
 
-func genericDestroy(s store, model *Model, quoter quoter) error {
+func genericDestroy(s store, model *Model, quoter quotable) error {
 	stmt := fmt.Sprintf("DELETE FROM %s WHERE %s", quoter.Quote(model.TableName()), model.whereID())
 	_, err := genericExec(s, stmt, model.ID())
 	if err != nil {