feat(options): Improve validation for parsers internal options (#29)

[soft-decay]

This is now completed.

• feat(options-v2): Improve options validation for svelte v2 parser
• test(options-v2): Add unit and integration tests for v2 options validation
• feat(options-v3): Improve options validation for svelte v3 parser
• test(options-v3): Add unit and integration tests for v3 options validation
• refactor: move ast options from parsers to lib/options
• refactor(v2-parser): extract function for sourceCode generation

[soft-decay]

Please tell me if anything else is missing before merging this PR.