v0.18.0: AWS Redshift DDL dialect support

Features

1. Added base support fot AWS Redshift SQL dialect.
   Added support for ENCODE property in column.
   Added new --output-mode='redshift' that add to column 'encrypt' property by default.
   Also add table properties: distkeys, sortkey, diststyle, encode (table level encode), temp.

Supported Redshift statements: SORTKEY, DISTSTYLE, DISTKEY, ENCODE

CREATE TEMP / TEMPORARY TABLE

syntax like with LIKE statement:

create temp table tempevent(like event);