use getNewLine from host rather than sys

Author: alexeagle

src/compiler/program.ts

@@ -1003,7 +1003,7 @@ namespace ts {
  }
 
  const category = DiagnosticCategory[diagnostic.category].toLowerCase();
- output += `${ category } TS${ diagnostic.code }: ${ flattenDiagnosticMessageText(diagnostic.messageText, sys.newLine) }${ sys.newLine }`;
+ output += `${ category } TS${ diagnostic.code }: ${ flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine()) }${ host.getNewLine() }`;
  }
  return output;
  }