Support Mysql REPLACE statement and PRIORITY clause of INSERT

[emin100]

New feature support

• Mysql replace statement was added
• Mysql insert and replace statement priority part were added

Examples:

REPLACE DELAYED INTO tasks (title, priority) VALUES ('Test Some Inserts', 1)

INSERT HIGH_PRIORITY INTO tasks (title, priority) VALUES ('Test Some Inserts', 1)

[coveralls]

Pull Request Test Coverage Report for Build 7308586737

• 115 of 119 (96.64%) changed or added relevant lines in 4 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.05%) to 87.732%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/parser/mod.rs	19	20	95.0%
src/ast/mod.rs	12	15	80.0%

Files with Coverage Reduction	New Missed Lines	%
src/ast/mod.rs	2	79.28%

Totals
Change from base Build 7303175792:	0.05%
Covered Lines:	18401
Relevant Lines:	20974

---

💛 - Coveralls

[alamb]

Retrigger CI

[alamb]

Thank you for the contribution @emin100 -- I think this is looking pretty close. I left some suggestions for your consideration.

[emin100]

@alamb thanks for the suggestions. I changed the pr.

[alamb]

Thank you @emin100 -- this is looking quite close. Thank you for sticking with it

[emin100]

@alamb If possible, can you release a new version that includes this change?

[alamb]

Thank you @emin100 -- this looks good to me. Thank you for sticking with it