Refactoring analyzer_cli for code hygiene.

pkg/analyzer_cli/lib/src/error_formatter.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer_cli.src.error_formatter;
 
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer_cli/src/analyzer_options.dart';
 import 'package:analyzer_cli/src/ansi.dart';
-import 'package:analyzer_cli/src/options.dart';
 import 'package:path/path.dart' as path;
 
 /// Returns the given error's severity.
 ProcessedSeverity _severityIdentity(AnalysisError error) =>
     new ProcessedSeverity(error.errorCode.errorSeverity);
 
 String _pluralize(String word, int count) => count == 1 ? word : word + "s";
 
 /// Returns desired severity for the given [error] (or `null` if it's to be
 /// suppressed).
@@ skipping 365 matching lines @@
   final ErrorSeverity severity;
   final bool overridden;
   ProcessedSeverity(this.severity, [this.overridden = false]);
 }
 
 /// Given an absolute path, return a relative path if the file is contained in
 /// the current directory; return the original path otherwise.
 String _relative(String file) {
   return file.startsWith(path.current) ? path.relative(file) : file;
 }