Cleanup assets folder

[Kruhlmann]

The assets folder is getting pretty crowded. I propose we move all images; png/svg/jpg to assets/img/ and all fonts to assets/fonts/. I will make a PR for this.

The following files will need updates to their references. (output of grep -e 'assets\/.*\.png' -e 'assets\/.*\.svg' -e 'assets\/.*\.jpg' -e 'assets\/.*\.woff2' . -R | grep -v node_modules | grep -v tags | grep -v dist). A total of 62 replacements needs to be made.

./ui/elemental_shaman/_sim.scss:	--theme-background-image: url('/wotlk/assets/elemental_shaman_background.jpg');
./ui/feral_druid/_sim.scss:	--theme-background-image: url('/wotlk/assets/feral_druid_background.jpg');
./ui/retribution_paladin/_sim.scss:	--theme-background-image: url('/wotlk/assets/retribution_paladin.jpg');
./ui/protection_warrior/_sim.scss:	--theme-background-image: url('/wotlk/assets/protection_warrior_background.jpg');
./ui/hunter/_sim.scss:	--theme-background-image: url('/wotlk/assets/hunter_background.jpg');
./ui/smite_priest/_sim.scss:	--theme-background-image: url('/wotlk/assets/smite_priest_background.jpg');
./ui/index.html:            src: url(/wotlk/assets/PlusJakartaSans-Regular.woff2);
./ui/index.html:            src: url(/wotlk/assets/PlusJakartaSans-Bold.woff2);
./ui/index.html:            background-image: url("assets/wotlk.jpg");
./ui/index.html:        <img src="/wotlk/assets/WoW-Simulator-Icon.png" style="height: 75px;">
./ui/index.html:                    <img src="/wotlk/assets/raid_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/balance_druid_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/feral_druid_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/feral_druid_tank_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/hunter_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/mage_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/retribution_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/protection_paladin_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/shadow_priest_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/smite_priest_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/rogue_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/elemental_shaman_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/enhancement_shaman_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/warlock_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/warrior_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/protection_warrior_icon.png" class="sim-title-icon">
./ui/index.html:                    <img src="/wotlk/assets/death_knight_icon.jpg" class="sim-title-icon">
./ui/warlock/_sim.scss:	--theme-background-image: url('/wotlk/assets/warlock_background.jpg');
./ui/enhancement_shaman/_sim.scss:	--theme-background-image: url('/wotlk/assets/enhancement_shaman_background.jpg');
./ui/core/proto_utils/action_id.ts:	[ResourceType.ResourceTypeBloodRune]: '/wotlk/assets/blood_rune.png',
./ui/core/proto_utils/action_id.ts:	[ResourceType.ResourceTypeFrostRune]: '/wotlk/assets/frost_rune.png',
./ui/core/proto_utils/action_id.ts:	[ResourceType.ResourceTypeUnholyRune]: '/wotlk/assets/unholy_rune.png',
./ui/core/proto_utils/action_id.ts:	[ResourceType.ResourceTypeDeathRune]: '/wotlk/assets/death_rune.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecBalanceDruid]: '/wotlk/assets/balance_druid_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecElementalShaman]: '/wotlk/assets/elemental_shaman_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecEnhancementShaman]: '/wotlk/assets/enhancement_shaman_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecFeralDruid]: '/wotlk/assets/feral_druid_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecFeralTankDruid]: '/wotlk/assets/feral_druid_tank_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecHunter]: '/wotlk/assets/hunter_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecMage]: '/wotlk/assets/mage_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecRogue]: '/wotlk/assets/rogue_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecRetributionPaladin]: '/wotlk/assets/retribution_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecProtectionPaladin]: '/wotlk/assets/protection_paladin_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecShadowPriest]: '/wotlk/assets/shadow_priest_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecWarlock]: '/wotlk/assets/warlock_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecWarrior]: '/wotlk/assets/warrior_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecProtectionWarrior]: '/wotlk/assets/protection_warrior_icon.png',
./ui/core/proto_utils/utils.ts:	[Spec.SpecSmitePriest]: '/wotlk/assets/smite_priest_icon.png',
./ui/core/proto_utils/utils.ts:export const raidSimIcon: string = '/wotlk/assets/raid_icon.png';
./ui/core/_sim_ui.scss:	mask: url(/wotlk/assets/gauge.svg);
./ui/core/_sim_ui.scss:	-webkit-mask: url(/wotlk/assets/gauge.svg);
./ui/core/_shared.scss:	src: url(/wotlk/assets/PlusJakartaSans-Regular.woff2);
./ui/core/_shared.scss:	src: url(/wotlk/assets/PlusJakartaSans-Bold.woff2);
./ui/core/sim_ui.ts:		// downloadBinary.src = "/wotlk/assets/gauge.svg"
./ui/protection_paladin/_sim.scss:	--theme-background-image: url('/wotlk/assets/prot_paladin.png');
./ui/warrior/_sim.scss:	--theme-background-image: url('/wotlk/assets/warrior_background.jpg');
./ui/shadow_priest/_sim.scss:	--theme-background-image: url('/wotlk/assets/shadow_priest_background.jpg');
./ui/balance_druid/_sim.scss:	--theme-background-image: url('/wotlk/assets/balance_druid_background.jpg');
./ui/rogue/_sim.scss:	--theme-background-image: url('/wotlk/assets/rogue_background.jpg');
./ui/feral_tank_druid/_sim.scss:	--theme-background-image: url('/wotlk/assets/feral_druid_tank_background.jpg');
./ui/mage/_sim.scss:	--theme-background-image: url('/wotlk/assets/mage_background.jpg');
./ui/deathknight/_sim.scss:	--theme-background-image: url('/wotlk/assets/death_knight_background.jpg');