feat: support ALIGN TO and Interval in Range query

[Taylor-lagrange]

Interval Support

The Interval expr can follow after RANGE and ALIGN keyword. Must use parentheses in interval, otherwise it will cause syntax conflicts

Case like:

SELECT 
    rate(a) RANGE (INTERVAL '1 year 2 hours 3 minutes') 
FROM 
    t 
    ALIGN (INTERVAL '1 year 2 hours 3 minutes')
FILL NULL;

ALIGN TO support

Support ALIGN TO sub clause, user cam use ALIGN TO to align to the time they want

SELECT rate(a) RANGE '6m' FROM t ALIGN '1h' TO '2021-07-01 00:00:00' by (a, b) FILL NULL;

Rewrite format

Rewrite format now be change to range_fn(func, range, fill, byc, [byv], align, to)

[coveralls]

Pull Request Test Coverage Report for Build 7029778735

• 30 of 33 (90.91%) changed or added relevant lines in 3 files are covered.
• 74 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.02%) to 83.208%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/parser/mod.rs	27	30	90.0%

Files with Coverage Reduction	New Missed Lines	%
src/lib.rs	4	11.15%
src/tokenizer.rs	10	86.43%
src/parser/mod.rs	60	80.17%

Totals
Change from base Build 6765669304:	-0.02%
Covered Lines:	16610
Relevant Lines:	19962

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💛 - Coveralls

[waynexia]

LGTM