ON SUNDAY, IRS officer and deputy director of Directorate of Revenue Intelligence (DRI) Shankhesh Mehta got a pat from his association — Indian Revenue Service Association. The applause that came in the micro-blogging site Twitter was for something spectacular -- the chasing of betel-nut smugglers in Surat and for a search that continued for 72 hours. So, who is Mehta, and what precisely was the appreciation for him? The IRS Association said…