Graph.get_edge():  handle exception correctly when no edge found
Graph.get_edge():  handle exception correctly when no edge found

--HG--
extra : convert_revision : svn%3A3ed01bd8-26fb-0310-9e4c-ca1a4053419f/networkx/trunk%40492

dhimmel/networkx,jtorrents/networkx,NvanAdrichem/networkx,kai5263499/networkx,blublud/networkx,harlowja/networkx,dmoliveira/networkx,bzero/networkx,dhimmel/networkx,tmilicic/networkx,ghdk/networkx,kai5263499/networkx,RMKD/networkx,ltiao/networkx,dmoliveira/networkx,farhaanbukhsh/networkx,harlowja/networkx,jtorrents/networkx,blublud/networkx,blublud/networkx,kernc/networkx,OrkoHunter/networkx,ionanrozenfeld/networkx,jakevdp/networkx,beni55/networkx,bzero/networkx,sharifulgeo/networkx,yashu-seth/networkx,jcurbelo/networkx,farhaanbukhsh/networkx,jni/networkx,jfinkels/networkx,JamesClough/networkx,kai5263499/networkx,andnovar/networkx,bzero/networkx,nathania/networkx,nathania/networkx,sharifulgeo/networkx,sharifulgeo/networkx,aureooms/networkx,ionanrozenfeld/networkx,debsankha/networkx,ionanrozenfeld/networkx,wasade/networkx,dhimmel/networkx,jakevdp/networkx,ghdk/networkx,farhaanbukhsh/networkx,kernc/networkx,kernc/networkx,ghdk/networkx,chrisnatali/networkx,dmoliveira/networkx,jni/networkx,aureooms/networkx,michaelpacer/networkx,chrisnatali/networkx,nathania/networkx,Sixshaman/networkx,jakevdp/networkx,chrisnatali/networkx,RMKD/networkx,aureooms/networkx,goulu/networkx,cmtm/networkx,debsankha/networkx,jni/networkx,harlowja/networkx,SanketDG/networkx,RMKD/networkx,debsankha/networkx