Pre-Release 3.0.0a4

• Relaxed pyparsing dependency requirements to allow for use of 3.2 and above for
  supported Python versions.
• Relaxed numpy dependency requirements to allow for use of 2.x and above for
  supported Python versions.
• Relaxed pydantic dependency requirements to allow for use of 2.x and above for
  supported Python versions.
• Relaxed pillow dependency requirements to allow for use of 8.x and above for
  supported Python versions.
• Relaxed click dependency requirements to allow for use of 8.x and above for
  supported Python versions.
• Relaxed Python version requirement to allow for use of 3.8 and above.
• Removed pygerber.sequence_tools module.
• Removed pygerber.frozen_general_model module.
• Removed pygerber.gerber.linter.diagnostic module.
• Removed pygerber.warnings module.
• Updated documentation links to point to stable release documentation.
• Renamed GerberX3Builder.add_trace() to GerberX3Builder.add_line_trace() to be
  consistent with GerberX3Builder.add_clockwise_arc_trace() and
  GerberX3Builder.add_counter_clockwise_arc_trace().
• Added support for Altium implied leading zeros omitted. Contributed by @sjgallagher2
  in #340.
• Added arc drawing in GerberX3Builder.
• Added region statement generation to GerberX3Builder.
• Added Gerber to PNG, JPEG, TIFF, BMP, WEBP and SVG conversion commands to CLI.
• Added Gerber format command to CLI.
• Extended documentation.