* Add import placement codestyle option

* Add TextEditor CodeStyle options for Using Placement

* Add misplaced using directives analyzer and code fix

* Use consistent pluralization

* Removed Preserve AddImportPlacement option

* Removed Preserve from CSharp Style Options

* Removed Preserve from editorconfig tests

* Coverted to Roslyn style analyzer and fixer tests.

* Simplified MisplacedUsings CodeFix based on feedback.

* Simplified MisplacedUsings CodeFix based on feedback.

* Add warning annotation to moved using directives

* Move misplaced usings out of multiple namespaces

* Deduplicate usings when moving them

* Simplified move usings warning text

* Add expected warning markers to misplaced using tests

* Fix editor config generator tests

* Consolidated diagnostics and tests

* Add tests where directives are in both contexts

* Fixes #34684

* Change from .Net to .NET

* update xlf files

This is a reworked version of #32616 targeting the dev16.0-preview3 branch.

Closes #31032

This ports https://github.com/dotnet/roslyn/pull/28472, that went into the `editorconfig-ide` feature branch, into `dev16.0.x` branch with following additional refactorings/enhancements:

1. Generated .editorconfig file has all localized string as comments.
2. No hardcoding of individual options in the editorconfig file generator. Instead, each `EditorConfigStorageLocation` now requires to provide a delegate to convert a given option value into the .editorconfig string representation (basically complimentary of the parsing delegate that was already required).
3. Introduce concept of `OptionGroup` to enable grouping options in the same feature (such as CodeStyleOptions, CSharpCodeStyleOptions, FormattingOptions, CSharpFormattingOptions, etc.) into sub-features or groups (such as "this. preferences", "expression-level preferences", etc.). This enables the editorconfig generation to group the related options, without explicit knowledge of each option group.
4. Expose `AllOptions` from each option feature (such as CodeStyleOptions, CSharpCodeStyleOptions, FormattingOptions, CSharpFormattingOptions, etc.), so that the corresponding `IOptionProvider` always stays in sync with implemented options.

* update UI text strings

* update string: Apply expression/block body preferences

* remove usings when format document

* sort usings when format document

* add code fix

* hack fix for the issue with apply multiple changes.

* refactoring

* 3 changes

1. put open file editorconfig change tracking back
2. handle open file leaking when solution close with files opened case
3. don't share locks between editorconfig events and roslyn events

* skip the 'Remove unused variable' when format document

* changed code fix part to use "fix all" and only fixes P1 list rather than fix everything in the document. also not apply changes to buffer until everything is done rather than doing it per fix.

* made undo experience better

* add expression body as one of fix to offer

* add code fix options in format document settings

* add hidden box IsCodeCleanupConfiguredCheckBox to track if the user ever configured the code cleanup

* clean up

* fix some tests

* disable a test temporarily

* PR comments

* refactoring

* Revert "3 changes"

This reverts commit 7e0fd53f02a0e20d063440b3cce5569e51e71afc.

* PR comments

* PR comments

* renaming

* bug fixing

* PR comments

* refactoring

* refactoring

* refactoring

* refactoring

* Make ICodeCleanupService extend ILanguageService

* refactoring

* refactoring

* fix deadlock, call Format inside CodeCleanupService

* rename async methods

* PR comments

* move files under features

* PR comments

* PR comments

* Never Show this again will never show the code cleanup info bar for this user.

* rename

* use ImmutableArray