clean up use of modules

src/dialect/mod.rs

@@ -0,0 +1,18 @@
+mod ansi_sql;
+mod generic_sql;
+pub mod keywords;
+mod postgresql;
+
+
+pub use self::ansi_sql::AnsiSqlDialect;
+pub use self::generic_sql::GenericSqlDialect;
+pub use self::postgresql::PostgreSqlDialect;
+
+pub trait Dialect {
+    /// Get a list of keywords for this dialect
+    fn keywords(&self) -> Vec<&'static str>;
+    /// Determine if a character is a valid identifier start character
+    fn is_identifier_start(&self, ch: char) -> bool;
+    /// Determine if a character is a valid identifier character
+    fn is_identifier_part(&self, ch: char) -> bool;
+}