Encapsulate Insert and Delete into specific structs

[tisonkun]

cc @alamb

This refers to #1204 where we will pull out some of the higher level enum variants into their own Structs for easier use

[alamb]

I don't think it matters, but just FYI you can do the same thing in the single let statement

Suggested change

	Statement::Insert(insert) => {
	let Insert {
	Statement::Insert(Insert {
	..
	}) => {

[tisonkun]

Thanks for your comment! I'll remember this and update this snippet when I have some time. You're correct. I just follow the intuitive "refactor" :D

[coveralls]

Pull Request Test Coverage Report for Build 8697518764

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 36 of 40 (90.0%) changed or added relevant lines in 5 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.001%) to 88.09%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/ast/mod.rs	25	29	86.21%

Totals
Change from base Build 8660968190:	0.001%
Covered Lines:	21287
Relevant Lines:	24165

---

💛 - Coveralls

[alamb]

Thank you @tisonkun -- while this will require downstream changes, I think they are mechanical and will be straightforward for users and this will make it easier to manage these statements going forward.

[tisonkun]

Thanks for your review and merge!