feat(databricks): add initial databricks syntax

[sjrusso8]

@andialbrecht & @mrmasterplan update my initial PR with the lexer changes. See below!

This PR will add frequently used Databricks and Delta table syntax. Databricks SQL has a lot of special operations to work with Delta tables which means a lot of new keywords.

Here is an example of standard operations of Databricks SQL for a created Delta table.

CREATE TABLE IF NOT EXISTS default.event 
(
    id INT, 
    name STRING, 
    description VARCHAR(30)
)
USING delta
LOCATION '/mnt/data/location'
PARTITIONED BY (id)
COMMENT 'this is a comment'
TBLPROPERTIES (
    'foo'='bar',
    delta.autoOptimize.optimizeWrite = true, 
    delta.autoOptimize.autoCompact = true
);

OPTIMIZE event 
WHERE date >= current_timestamp() - INTERVAL 1 day 
ZORDER BY (id);

VACUUM event;

CREATE BLOOMFILTER INDEX ON TABLE event 
FOR COLUMNS(description OPTIONS (fpp=0.1, numItems=50000000));

CREATE TABLE default.event_clone SHALLOW CLONE default.event;

DESCRIBE HISTORY event;

DESCRIBE TABLE EXTENDED event;

SHOW DETAIL event;

MSCK REPAIR TABLE event SYNC METADATA;

REFRESH TABLE event;

Then operating on those statements should parse out additional keywords like below.

statements = sqlparse.parse(sql)

for statement in statements:
    result = [v.value for v in sqlparse.sql.IdentifierList(statement.tokens).get_identifiers() if v.is_keyword]

    print(result)

>>> ['CREATE', 'TABLE', 'IF', 'NOT', 'EXISTS', 'USING', 'LOCATION', 'PARTITIONED BY', 'COMMENT', 'TBLPROPERTIES']
>>> ['OPTIMIZE', 'ZORDER BY']
>>> ['VACUUM']
>>> ['CREATE', 'BLOOMFILTER INDEX', 'ON', 'TABLE', 'FOR']
>>> ['CREATE', 'TABLE', 'SHALLOW CLONE']
>>> ['DESCRIBE', 'HISTORY']
>>> ['DESCRIBE', 'TABLE', 'EXTENDED']
>>> ['SHOW', 'DETAIL']
>>> ['MSCK REPAIR', 'TABLE', 'SYNC', 'METADATA']
>>> ['REFRESH', 'TABLE']