Working references

[tomblachut]

This ~is a very rough take to get rid of~ removes faulty code injector and make whole plugin robust at last by using lazy parsing. No more weird inspections, switch to JSX prompts. Even intentions like Remove parentheses work.

Completion popups need to get care after this.

Resolves #3

[tomblachut]

Work on this PR gave me better outlook on the next steps:

• Attributes should also be handled by lazy parsing (Angular does this) - that requires tinkering with SvelteHTMLLanguage and SvelteJSReferenceExpressionResolver introduced in said #50. (#2)
• <Foo {name}> will require changes to HTML lexer/parser and also fixing missing required attributes inspections - VueXmlExtension#isRequiredAttributeImplicitlyPresent` i think handles that.
• <Foo prop={name}> without quotes is a similar story, I don't know yet but there can be issues with escape characters. (#22)
• For use:function to work function must have a reference. IDK about best approach here but for sure injection is not required. (#11)
• Work on $ labels is blocked by me figuring out how to parse JS inside script as custom SvelteJS with working references. Currently I've switched JS from default dialect to ES6 module which fixes some things but isn't extensible. (#7)
• Store $references are tricky. I think conditional lazy parsing is the best course of action here - there is some prior art with Angular parsing #ref as # & ref. I tried with reference contributor but find usages don't work then and extending those word scanners feels hacky. (#4)