Under Window → Preferences:

• set Encoding UTF-8: Expand left menu to General → Workspace:
  • Check Text file encoding and select:

    Other:
      UTF-8

  • Check New text file line delimiter and select:

    Other:
      Unix

• Ensure that spaces are used instead of tabs: Expand left menu to General → Editors → Text Editors
  • Check Insert spaces for tabs
  • Change Displayed Tab Width: 4
• Removing trailing whitespaces: Click left menu PHP→Editor→Save Actions: check Remove trailing whitespace and select All lines