New color themes?

[Bikes4Fun]

This request adds new color themes to the ColorTable class in PrettyTable. This provides users with built in options for customizing the appearance of their tables.

Changes made:

• Added 8 new themes to the Themes class in colortable.py:
  • FOREST
  • SUNSET
  • OCEAN_DEEP
  • LAVENDER
  • MONOCHROME
  • NEON
  • EARTH
  • PASTEL

Benefits:

1. Increased customization options for users
2. More variety in color schemes to suit different preferences and use cases
3. Includes themes with both basic and extended color palettes for compatibility with various terminal environments

Testing:

• Tested all new themes in multiple terminal environments to ensure compatibility
• Verified that existing functionality remains unchanged

Usage example:

[hugovk]

Looks good, would you like to open a PR?

[Bikes4Fun]

Yes please :)