made couriers invulnerable and map fixes/updates

GENERAL
===============
- Nightmare and Challenger unit counts are the same now, so no more double Necro bosses.
- Replaced the attack damage increase bosses get on Nightmare with a base attack time reduction, to better simulate more creeps attacking. Overall DPS is the same but a single attack is less punishing.

HEROES
===============
- Added following heroes by popular request, they are vanilla so if some of their abilities don't work on creeps don't report it we already know: Grimstroke, Monkey King, Oracle, Timbersaw, Nyx Assassin, Bounty Hunter, Witch Doctor, Chen, Dark Seer, Hunter, Earth Spirit, Meepo, Rubick
- Changed scaling of durations for abilities to be at maxed at all levels, unless duration is the primary source of scaling for the ability (abilities like Kinetic Field). Mostly affects buffing and debuffing abilities by making them longer duration level 1-3.
- Dragon Knight: Normalized Fireball damage values to be more in line with other nukes, more damage earlygame, less late.
- Wisp: Allies are now resurrected or restored to full health and mana if Wisp survives for the entire duration, rather than immediately. Duration is now 6 at all levels and the health sacrificed reduces per level instead.

ITEMS
===============
- Fixed Refresher Orb being refreshable by Ex Machina

BOSSES
===============
Round 1: Increased base gold from 1250 to 1500; maximum gold from 1875 to 2250

GENERAL
===============
- Fixed code cleanup causing the game to not be loseable.

HEROES
===============
- Medusa: Buffed Mana Snake mana steal and Mana Shield damage per mana.
- Luna: Fixed Lucent Beam damage

BOSSES
===============
Round 15: Reduced stun times and increased sk1 cooldown

treant boss crash fixes, hopefully
fixed luna and dp having vanilla values on talents and shards

removed seed shot from greater treants and nature's grasp from treants because it might be a source for crashes

less treants

Round 12: Reduced values on spells

GENERAL
===============
- Reduced spawn intervals of Challenger earlygame

HEROES
===============
- Warlock: Removed cooldown scaling on Fatal Bonds past Lv4, replaced with more bounces.

BOSSES
===============
- Round 2: Slightly reduced health and damage from units for all difficulties.
- Round 4: Reduced Zombling damage variance and slightly reduced damage on all difficulties

GENERAL
===============
- Capped gold multiplier scaling down past 7 players; meaning more starting gold in Nightmare but unchanged for other difficulties
- Summoned units no longer benefit from haste.
- Reduced the initial difficulty damage and health scaling slightly for all difficulties.

BOSSES
===============
- Round 2: Slightly reduced health and damage from units for all difficulties.

BOSSES
===============
- Round 1: Increased attack damage of Chest Mimics from 1-2 to 1000-2000
- Round 9: Increased damage of Fire Breath by 50% on all difficulties.
- Round 12: Ogre Magi now has Frost Shield, Ignite and Multi-Cast. No longer has Bloodlust.
- Round 12: Ogre Berserkers now have Bloodlust but only self-cast it. Also have Multi-Cast.
- Round 12: Troll Champion now has Whirling Axes and Axe Throw as well as Berserker's Blood.
- Round 12: Troll Champion now toggles between ranged and melee, prefering melee if possible or if needed to catch up to its target
- Round 12: Reduced total number of spawns.
- Round 13: Treant Boss no longer summons units. Now has Overgrowth, Living Armor, Nature's Grasp and Leech Seed. Living Armor is an area of effect, but Treant Boss will prioritize targeting himself if he does not have the buff.
- Round 13: Nature's Prophet now has Sproud and Wrath of Nature. Call of Nature summons up to a certain number of Greater Treants by destroying trees on the map, cannot summon Treants if there are no trees. Wrath of Nature creates one Lesser Treant for each unit it hits.
- Round 13: Greater Treants have Seed Shot
- Round 22: Fixed Shadow Fiend boss razes not dealing damage.