Release v1.3.0

• New features:
  • Files Explorer:
    • You can select multiple Python files at same time, without using "Open File" manually.
    • Icons for Folders, Python files, Markdown files, and the rest are Unknown files.
  • View menu:
    • Toggle Files Explorer
    • Toggle Lines Number
  • Updater: Checks if there are any new updates or not.
• Small Bug fixes:
  • When installing packages, the shell of pip packages manager shows up for no reason.
  • Redraw Line Numbers if there are any Key pressed, including "Enter" (which is "Return").