Check if a token is valid

Property definitions

github $ GithubWallet :: check_token
	# Check if a token is valid
	fun check_token(token: String): Bool do
		logger.debug "Try token {token}"
		var api = new GithubAPI(token)
		api.get_auth_user
		return not api.was_error
	end
lib/github/wallet.nit:146,2--152,4