v2.4.0 - Backgrounding

• Enables the creation of backgrounds on the PDFs
  • Gray > --background-gray <percentage>
  • RGB > --background-rgb <"R G B">
  • CMYK > --background-cmyk <"C M Y K">
• Will paint a colored box behind the document
• Updated help and readme for background creation
• Will bypass creation if no background is set
• Added many helper functions do validate and process colors and numbers
• Color specifications must be quoted as a single parameter