By Rajesh Kumar Singh NEW DELHI (Reuters) – Parliamentary obstruction scuppered Prime Minister Narendra Modi's economic agenda in a month-long session that ended on Tuesday, and the prospect of further deadlock means he will find it hard to deliver quickly on promises of reform. Lawmakers left without voting on a long-delayed bill to raise the cap on foreign investment in insurance companies to 49 percent from 26 percent, and another that would overhaul the troubled coal sector. …