[FEATURE] Support date and time functions

[Yury-Fridlyand]

Copied from https://github.com/opendistro-for-elasticsearch/sql/issues/709.

Implementation should match MySQL standard: https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html

• [x] date
• [x] time
• [x] timestamp
• [x] adddate
• [x] date_add
• [x] date_format
• [x] date_sub
• [x] dayname
• [x] dayofweek
• [x] dayofmonth
• [x] dayofyear
• [x] from_days
• [x] makedate - #755
• [x] maketime- #755
• [x] monthname
• [x] hour
• [x] minute
• [x] second
• [x] microsecond
• [x] day
• [x] week
• [x] month
• [x] quarter
• [x] year
• [x] subdate
• [x] time_to_sec
• [x] to_days
• [ ] addtime
• [ ] adddate
• [ ] convert_tz - #848
• [x] curdate - #754
• [x] current_date - #754
• [x] current_time - #754
• [x] current_timestamp - #754
• [x] curtime - #754
• [ ] datediff
• [ ] datetime - #848
• [ ] date_add (update)
• [ ] date_sub (update)
• [ ] day_of_month
• [ ] day_of_year
• [ ] extract
• [ ] hour_of_day
• [ ] from_unixtime - #835
• [ ] get_format
• [ ] last_day
• [x] localtime - #754
• [x] localtimestamp - #754
• [ ] minute_of_day
• [ ] minute_of_hour
• [ ] month_of_year
• [x] now - #754
• [ ] period_add - #933
• [ ] period_diff - #933
• [ ] sec_to_time
• [ ] second_of_minute
• [ ] str_to_date
• [ ] subtime
• [x] sysdate - #754
• [ ] time
• [ ] timediff/time_diff
• [ ] timestamp
• [ ] timestampadd
• [ ] timestampdiff
• [ ] time_format
• [ ] to_seconds
• [ ] unix_timestamp - #835
• [ ] utc_date
• [ ] utc_time
• [ ] utc_timestamp
• [ ] weekday
• [ ] weekofyear/week_of_year
• [ ] yearweek
• [ ] >/=/< (comparison operators for datetime types)

Further improvements:

• [ ] #859
• [ ] #861
• [ ] #862
• [ ] #853
• [ ] #852
• [ ] #855