LONDON (Reuters) - Stock index futures pointed to a higher open on Wall Street on Tuesday, with futures for the S&P 500, the Dow Jones and the Nasdaq 100 rising 0.1 to 0.2 percent. Market sentiment improved after Euro zone finance ministers and the International Monetary Fund clinched agreement late on Monday on reducing Greece's debt in a breakthrough to release urgently needed loans to keep the near-bankrupt economy afloat. The Commerce Department releases October durable goods orders at 8.30 a.m. ET. Economists expect a 0.6 percent fall in orders in October, against a 9. ...