[DOC]:Document Impala support for Kudu DATE type

---- QUERY
# create table with primary key of DATE type
create table kudu_date_key (fdatekey date primary key, val string)
stored as kudu
---- RESULTS
'Table has been created.'
---- ERRORS
Unpartitioned Kudu tables are inefficient for large data sizes.
====
---- QUERY
insert into kudu_date_key values (DATE '1970-01-01', 'Unix epoch'), (DATE '2019-12-12', 'today')
---- RUNTIME_PROFILE
NumModifiedRows: 2
NumRowErrors: 0
---- LABELS
FDATEKEY,VAL
---- DML_RESULTS: kudu_date_key
1970-01-01,'Unix epoch'
2019-12-12,'today'
---- TYPES
DATE,STRING
====
---- QUERY
# create table with DATE primary key partitioned by range
create table kudu_datepk_range (fdate DATE not null primary key)
partition by range (fdate)
(
  partition values < DATE '1900-01-01',
  partition DATE '1900-01-01' <= values < DATE '1970-01-01',
  partition DATE '1970-01-01' <= values < DATE '2000-01-01',
  partition DATE '2000-01-01' <= values
)
stored as kudu
---- RESULTS
'Table has been created.'
====
---- QUERY
insert into kudu_datepk_range values
  (DATE '1800-01-01'),
  (DATE '1970-01-01'),
  (DATE '2019-12-12')
---- RUNTIME_PROFILE
NumModifiedRows: 3
NumRowErrors: 0
---- LABELS
FDATE
---- DML_RESULTS: kudu_datepk_range
1800-01-01
1970-01-01
2019-12-12
---- TYPES

DATE
====
---- QUERY
select * from kudu_datepk_range;
---- RESULTS
1800-01-01
1970-01-01
2019-12-12
---- TYPES
DATE
====---- QUERY# Test date columns and primary keycreate table describe_date_test( date_pk date PRIMARY KEY, date_val date not null, date_null date null)stored as kudu;describe describe_date_test;---- LABELSNAME,TYPE,COMMENT,PRIMARY_KEY,NULLABLE,DEFAULT_VALUE,ENCODING,COMPRESSION,BLOCK_SIZE---- RESULTS'date_pk','date','','true','false','','AUTO_ENCODING','DEFAULT_COMPRESSION','0''date_val','date','','false','false','','AUTO_ENCODING','DEFAULT_COMPRESSION','0''date_null','date','','false','true','','AUTO_ENCODING','DEFAULT_COMPRESSION','0'---- TYPESSTRING
====