Sizable update, v0.7

Lots of updates, some little and some big! I decided to codify some of the lore and setting ideas in my head into the actual book, like the differences between a jotunn and a colossus.

v0.7

• Added new Monster Types section, with descriptions and icons for each of the different monster types
• Added icons throughout, identifying each type of monster with an icon
• Added Damage Modifiers and Conditions sections
• Added Creating Monsters section (WIP)
• Added Converting Monsters section (WIP)
• Added new image for muspelhound
• Added new image for skeleton
• Added weakness to fire beetle, fire colossus, frost colossus, Dragon of the Mists, Eagle of the Glacier, gargoyle, fire jotunn, frost jotunn, jotunn of ash, lindworm, muspelhound, giant octopus, fire ooze, shambling mound, white worm
• Updated entry for Bull of the Stone to add resistance and update bellow
• Added missing image captions and corrected format
• Corrected colours to be more consistent
• Added in Inspiration, Thanks, and Patrons (WIP) section on ToC page