Partial GameManager documentation

[Tyegurr]

Added documentation for:

GameManager::get()
GameManager::update(float)
GameManager::init()
GameManager::acountStatusChanged()
GameManager::activeIconForType(IconType)
GameManager::doQuickSave()
GameManager::getPlayerBall()
GameManager::getPlayerBird()
GameManager::getPlayerColor()
GameManager::getPlayerColor2()
GameManager::getPlayerDart()
GameManager::getPlayerDeathEffect()
GameManager::getPlayerFrame()
GameManager::getPlayerGlow()
GameManager::getPlayerGlowColor()
GameManager::getPlayerJetpack()
GameManager::getPlayerRobot()
GameManager::getPlayerShip()
GameManager::getPlayerSpider()
GameManager::getPlayerStreak()
GameManager::getPlayerSwing()
GameManager::getPLayLayer()