Documentation Fix - Mod Events

dota_player_used_ability,
dota_player_learned_ability,
dota_player_gained_level,
The key has "player" property instead of "PlayerID".

dota_item_picked_up,
The keys has more properties namely "ItemEntityIndex" and
"HeroEntityIndex".
Documentation Fix - Mod Events

dota_player_used_ability,
dota_player_learned_ability,
dota_player_gained_level,
The keys has "player" property instead of "PlayerID".

dota_item_picked_up,
The keys has more properties namely "ItemEntityIndex" and
"HeroEntityIndex".
Merge pull request #139 from D-storm/master

Documentation Fix - for Mod Events wrong key values were corrected